[BBC.CO.UK] Germany's Angela Merkel...current chancellor of Germany. She was educated in East Germany when is was still run by commies, but in 1989 got involved with the growing democracy movement when the Berlin Wall fell. Merkel is sometimes referred to by Germans as
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has said a US official's apparent insult of the EU's efforts to mediate in the Ukraine crisis is "totally unacceptable".
Victoria Nuland has apologised after she referred disparagingly to the EU's role during a conversation said to be with the US ambassador to Ukraine.
A recording of the exchange was posted online, with the US hinting at Russia's involvement in bugging and leaking it.
The EU and US are involved in talks to end months of unrest in Ukraine.
In Kiev, Ms Nuland - an assistant secretary of state - said she would not make a public statement on the matter.
She described the leak as "pretty impressive tradecraft. [The] audio quality was very good".
The state department said she had apologised in private to EU officials.
Mass anti-government protests erupted in Ukraine in late November after President Viktor Yanukovych refused to sign a far-reaching association and trade agreement with the EU - under heavy pressure from Moscow.
Russia has been widely accused of using its economic clout to persuade Mr Yanukovych not to pursue closer ties with Brussels.
Russia has itself accused Washington and the EU of meddling in Ukraine.
German government spokeswoman Christiane Wirtz said Ms Merkel fully supported the work done by EU foreign policy chief Catherine Ashton to find a solution to the crisis.