The Justice Department said Monday morning it has cleared networking giant Cisco Systems Inc.’s  bid to acquire video conferencing provider Tandberg ASA. In a statement, the agency emphasized it had “cooperated closely” with its European counterparts in reviewing the deal, a sign of a smoother relationship between Brussels and Washington D.C., after the two agencies clashed on a similar deal earlier this year.

Cisco, Tandberg, and other industry participants signed waivers for the Antitrust Division and the European Commission’s Directorate General for Competition to share information and coordinate on potential remedies to ensure interoperability between Cisco’s new teleconferencing products and those of other companies. The Justice Department said it had taken those commitments into account, along with other factors, in reaching its determination not to challenge the deal.

“This investigation was a model of international cooperation,” Antitrust chief Christine Varney said in a statement. “The parties should be commended for making every effort to facilitate the close working relationship between the Department of Justice and the European Commission.”

The two agencies clashed last year in reviewing database software provider Oracle Corp.’s $7.4 billion purchase of Sun Microsystems Inc. The Justice Department OK’d the deal last summer, but European Union officials issued a set of objections to the sale in early November.

The DOJ responded to those objections by saying the sale did not raise major anti-competitive concerns and nudged the E.U. to clear the transaction.  Brussels responded with visible annoyance, but eventually cleared the deal.

Then in November, the Justice Department hired E.U. antitrust expert Rachel Brandenburger as a new adviser on international matters. A better working relationship between the two agencies seemed to follow. When the DOJ signed off on Microsoft Corp.’s advertising pact with Yahoo! Inc. in February, for example, it waited until European regulators had announced a decision.

On the Cisco deal, the DOJ said it was satisfied with the commitments the company made to Brussels. Cisco promised that its teleconferencing products could operate with products from other companies. Cisco had already entered the videoconferencing business when it announced its $3 billion purchase of the Norwegian company last October. The E.U. announced its decision earlier today.

“The commitments are designed to foster the development of open operating standards,” the DOJ said in its statement. “The department views those commitments as a positive development that likely will enhance competition among producers of telepresence systems.”

Cisco could not immediately be reached for comment on how the trans-oceanic review was handled.

A trial attorney in the Justice Department’s Antitrust Division, Robert Mahnke, went to Brussels last week for a closed-door hearing on Oracle Corporation’s proposed purchase of Sun Microsystems, Inc., according to a person familiar with the matter.

After competition regulators in the European Union raised concerns about the $7.4 billion deal last month, the Justice Department issued a statement announcing it had not found the same concerns. The different conclusions led to a series of exchanges that highlighted public tension between the two agencies.

According to an attorney who was at the Oracle hearing, Mahnke, who works in the networks and technology section of the division, was in Brusses largely on a peace-keeping mission.

“He was reassuring people that the statement had been misrepresented, and reassuring people it was a bit of a blip. On most things [the two agencies] do see eye-to-eye,” said the attorney who spoke about the closed hearing on condition of anonymity.

A Justice Department spokeswoman did not respond to a request for comment.

While not unprecedented, observers say, the DOJ is not often represented at similar hearings in Europe. “It’s unusual but it seems like it’s a constructive step,” said Douglas Rosenthal, a partner at Constantine Cannon who previously served in the Antitrust Division as head of the foreign commerce section.

“Over the years there have been many meetings at which Europeans sent staff to talk about cases and vice versa,” he said. “It is the next step to be at a hearing.”

The trip comes amid a push on the part of American antitrust regulators to increase cooperation with their counterparts in Europe. Last month, the Antirust Division hired Rachel Brandenburger, a competition lawyer with Freshfields Bruckhaus Deringer in London and Brussels, as a new top adviser on international matters.

The differences over the Oracle-Sun deal involve Sun Microsystems’ open-source database software MySQL. While DOJ attorneys found that MySQL’s light databases catered a different market than Oracle’s heavier product, European regulators argued that MySQL was becoming a competitive threat to Oracle’s proprietary databases, raising the likelihood that Oracle wouldn’t continue to support and develop it.

After the hearing in Brussels, Oracle issued a set of commitments to protect the viability of MySQL. Despite heavy protests from the open-source community, the European Commission has signaled it is moving towards approving the deal.

Rachel Brandenburger (Freshfields)

The Justice Department’s Antitrust Division has recruited, from Brussels, a new top adviser for international matters, at a time when the Obama administration hopes to smooth over disputes between the U.S. and the European Union on antitrust issues.

The new adviser, Rachel Brandenburger, is an antitrust partner with the United Kingdom-headquartered Freshfields Bruckhaus Deringer and works out of the firm’s London and Brussels offices.

Brandenburger has expertise in counseling clients in cases in front of both the European Commission and UK regulators, according to the biography provided by her firm.

Brandenburger will  join the Division in January, and will report directly to Assistant Attorney General Christine Varney, according to Justice spokeswoman Gina Talmona. Brandenburger also will work closely with Philip Weiser, the Deputy Assistant Attorney General for International, Policy and Appellate Matters.

Brandenburger has worked closely with the American Bar Association’s antitrust section on international competition issues, and has connections to the American antitrust bar.

“She will be a very effective and valuable part of AAG Varney’s team in ensuring that the U.S. remains at the forefront of international competition matters going forward,” said the head of the ABA’s antitrust section, Ilene Gotts, a partner at Wachtell, Lipton, Rosen & Katz, who cites Brandenburger as one of her closest friends. “I am delighted to see this development occur.”

The hire adds visibility to international issues. The move to bring in an “all-star player” is to “upgrade the salience of the international function,” said Bert Foer of the American Antitrust Institute think tank.

Observers also acknowledge that such a hire is unusual, since few can remember another instance of either the Justice Department or the Federal Trade Commission hiring a European antitrust expert who is not a U.S. citizen. The E.U. and U.S. often disagreed on antitrust enforcement during the George W. Bush administration, which had a generally hands off approach. The jurisdictions previously cooperated primarily on price-fixing cases.

The announcement of Brandenburger’s hire follows weeks of public tension between the Antitrust Division and its counterpart in Brussels, the European Commission, over database software provider Oracle Corp.’s proposed purchase of Sun Microsystems Inc.

The Justice Department OK’d the $7.4 billion deal earlier this year, but European Union officials issued a set of objections to the sale in early November.

Molly Boast the Deputy Assistant Attorney General for Civil Matters, responded to those objections with a nudge to the EC to clear the deal. The sale did not raise major anti-competitive concerns, she said.

Fifty-nine members of the U.S. Senate followed up last week, with a letter urging European regulators to approve the deal.

Varney signaled early on in her tenure that the division’s relationship with the European Commission would be a high priority. “In this context of a global economy, divergence in substantive rules and procedural approaches poses significant difficulties for members of the business community,” Varney said in a September speech at Fordham University.

The new position has also been in the works for months, according to Talamona. “One of the first decisions Christine made”  was to hire ”somebody that specializes in international issues,” Talmona told Main Justice.

The search for a top person to fill the post began in April, but the “hiring process can take time,” she said.

Even if the timing is coincidental, antitrust attorneys privately acknowledge that bringing in a new adviser on international issues can help smooth further differences between Washington and Brussels. “Someone who is European can’t be accused of American arrogance,” said one antitrust attorney who spoke frankly about the hire in exchange for anonymity.

This article was updated at 4:05 p.m.