Argentina's move to nationalize local oil company YPF, controlled by Spain's Repsol, was a mistake and the wrong thing to do, the head of the World Bank said on Thursday.

It is mistake, World Bank President Robert Zoellick told a news conference at the opening of World Bank and International Monetary Fund meetings of finance chiefs in Washington.

I think it is a symptom we have to watch out for under economic pressure whether countries will move ... respond more to populism, respond more to protectionism, he said. I think it was the wrong thing to do.

(Reporting By Lesley Wroughton; Editing by Neil Stempleman)