Speaking to reporters following their meeting in Berlin on Friday, German Foreign Minister Steinmeier said tensions over revelations about mass surveillance conducted by the US National Security Agency (NSA) would not be allowed to ruin what he described as the "long-standing friendship" between the two countries.

“We will be successful in restoring trust … where trust has been destroyed,” Steinmeier said.

Kerry, who has conceded in the past that NSA activity may have sometimes gone too far, called for the two allies to look to the future and expressed optimism that the current tensions over the NSA affair would be overcome.

"I want to say to the German people that it's no secret that we've been through a rough period," Kerry said.

He also highlighted "a long history of great cooperation on complicated issues like counterterrorism, national security and defense" between the two countries.

Working together on Ukraine

Following their statements, the two top diplomats were also asked about a number of international issues, including the political standoff between the government and the opposition in Ukraine.

"The offers of President Yanukovych have not yet reached a level that would be sufficient regarding the reforms," Kerry said, referring to efforts by the Ukrainian leader to defuse that country's crisis. He also said the crisis was for the Ukrainian people to resolve and that "outside powers" should not get involved. At the same time, he said the US and Germany were working "shoulder to shoulder" on Ukraine.

Steinmeier warned that "we are a long way from a political solution [in Ukraine]."

This is Kerry's first trip to Germany since the NSA scandal broke last June, followed by the October allegation that it had bugged Chancellor Angela Merkel's mobile phone. This was among revelations that came to light through documents leaked by former NSA contractor Edward Snowden, who has been granted temporary asylum in Russia.

Kerry met with Chancellor Merkel at the Chancellery shortly after his meeting with Steinmeier. Later, he was to fly south to the Bavarian capital, where he is to attend the annual Munich Security Conference.

pfd/ph (dpa, Reuters)