By Kate Kelland
LONDON, March 31 (Reuters) - The G20 summit of world leaders this week will only succeed in tackling the global financial crisis if all nations commit to act together, Prime Minister Gordon Brown said on Tuesday.
The meeting of leading nations in London on Thursday is being billed as a turning point in efforts to deal with the world's biggest recession since the 1930s -- a downturn which has already destroyed major banks and cost millions of jobs.
"The world didn't come together in previous recessions and they lasted much longer," Brown told Good Morning Television. "And I think there is a determination on all our parts -- given that we are dealing with the same problems -- to take action."
"The most important thing is that we all act together, because if we act with other countries, it's got twice the effect than if we do it on our own."
The summit's draft statement, obtained by Reuters on Monday, shows leaders want to agree to avoid currency moves and protectionist measures that would damage other economies. It also repeats existing promises to get economies back on track, but does not contain any specific details.
Brown reiterated his hopes for the G20 to agree on measures to "clean up" the world's banking system, to inject money into economies, to create jobs, and "get trade moving again".
Stock markets around the world tumbled on Monday -- the latest dive in a crisis that has rolled on for nearly two years. Analysts say markets want clarity and conviction from the G20.
Brown said the leaders had made some progress "but we've got a lot more to do this week".
"We have got to have global action to make sure that people are more secure, and for the first time we are doing that," he said.
Brown said he understood public anger at the global recession, but warned it should not be allowed to boil over during protests expected in London this week.
He said the fact that the summit was being held in London was a "recognition of our importance as an economy for the future" and warned protesters not to try to disrupt the event.
"Most people who are making their views known are wanting to do so in a peaceful way," he said. "But no violence can be tolerated, no intimidation of people is allowed, and the police will act very quickly if there is any threat to property or people."
British police said on Monday that five people suspected of planning to protest were being held under counter-terrorism powers after weapons were found in a raid in southwest England.