U.K. Prime Minister Gordon Brown said on Wednesday that the United States and Europe must act together, echoing President Barack Obama's call for unity in tackling the global economic crisis.

"The greatest danger we face as trade starts to fall is that countries will resort to protectionist measures," Brown told The Wall Street Journal, ahead of next week's summit of the G20 in London.

Brown backed reform of global institutions like the International Monetary Fund and the World Bank in order to meet the challenges countries face now. Normally, those institutions have been tasked with financing developing countries, not unwinding an asset-driven catastrophe among developed countries such as the U.K. and the United States.

Obama this week made similar noises about unity ahead of the summit.

"We don't want a situation in which some countries are making extraordinary efforts and other countries aren't, with the hope that somehow the countries that are making those important steps lift everybody up," Obama in a televised news conference this week.