"Janet Yellen knows perfectly what the U.S. economy needs and she is perfectly aware of the implications that the economic policy of the United States is going to have on the world economy," Luis de Guindos said at a news conference.

"The appointment of Janet Yellen is good news for the U.S. economy and the global economy."

The ECB has criticised Donald Trump's outgoing administration for its protectionist stance and was attacked by the U.S. president over the euro-dollar exchange rate.

(Reporting By Francesco Canepa; Editing by Balazs Koranyi)