UPDATE 1-OECD, WTO, UN press G20 powers to keep markets open

GENEVA, Oct 31 (Reuters) - The world's leading economies must try harder to keep their markets open to counter slowing global growth, international agencies said on Wednesday.

The World Trade Organization, the OECD and UNCTAD said the G20 group of countries imposed fewer protectionist measures in the past five months, but the slow pace of recovery in foreign direct investment (FDI) was causing concern.

``Over the past five months, the global economy has encountered increasingly strong headwinds,'' the agencies said in a joint report.

``G20 governments need to redouble their efforts to keep their markets open and to advance trade opening as a way to counter slowing global economic growth.''

The three agencies issued their report, the latest in a semi-annual series, as a joint presentation for the leaders of the group, which comprises the world's richest powers and leading emerging economies.

Finance ministers and central bankers from the bloc are meeting this weekend in Mexico City.

In September, the WTO cut its growth forecast for world trade - a prime motor for the economy - to 2.5 percent from 3.7 percent for 2012 and to 4.5 percent from 5.6 percent for next year.