Ms Brainard's comments follow remarks earlier in the day from the head of Germany's influential Bundesbank, who warned eurozone politicians to stay away from talking down the euro, arguing that any policy to weaken the currency would lead to higher inflation.

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Some insiders have suggested to me that Mr Obama might plug this gap by promoting Lael Brainard, the Treasury's senior international official, to be Mr Lew's deputy, with an understanding that she would now take the lead in the administration on most international economic issues.

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The Mayor of Carmel, Jim Brainard, has become America's evangelist-in-chief on the matter, demolishing 78 sets of traffic lights and replacing them with those round islands so familiar to drivers in the UK. Four more will be finished in the coming months.

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"But such worries are receding as she (Ms Brainard) said she supports Japan's efforts to end deflation, " he added.

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We also have Lael Brainard, Under Secretary of the Treasury for International Affairs, and Mike McFaul, the U.S. Ambassador to Russia.

WHITEHOUSE: Press Briefing by Jay Carney and Ben Rhodes

And then, a follow up for Ms. Brainard as well, do you feel as though the Vice President will have to defend the U.S. and its position on debt and deficit?

WHITEHOUSE: Via Telephone