London  - British Prime Minister Gordon Brown set off Monday to become the first European leader to have talks with US President Barack Obama in Washington, expected to focus on the world economy and future military cooperation.

Officials in London said Brown was keen to deliver a "clear message" from Europe to Obama about the need for urgent worldwide action to counter the economic crisis.

The talks were described as a "make-or-break opportunity" to persuade the new US administration to engage in what Brown has called a "global new deal" to tackle the recession.

Sources said Brown was keen to hammer out details of a global economic recovery plan with Obama ahead of the summit meeting of Group of 20 (G20) nations in London on April 2.

Brown, bolstered by being the first European leader to have talks with Obama since the latter took office, hopes that the US President will "throw his weight" behind an ambitious outcome of the April summit, the Financial Times said.

At the same time, the encounter is of crucial value to Brown, whose ruling Labour Party is currently trailing by more than 10 percentage points behind the opposition Conservatives as Brown's self-proclaimed image of the "saviour of the world economy" is fading.

On Wednesday, Brown is due to give what has been described as a "highly personal" address to a joint session of Congress, becoming only the fifth British prime minister in history to be given the honour.

"I believe there is no challenge so great or so difficult that it cannot be overcome by America, Britain and the world working together," Brown wrote in the Sunday Times newspaper this week.

"Britain and America may be separated by the thousands of miles of the Atlantic, but we are united by shared values that can never be broken," he wrote.

"And as America stands at its own dawn of hope, I want that hope to be fulfilled through us all coming together to shape the 21st century as the first century of a truly global society," Brown added.

Talks are expected to go less smoothly, however, on the issue of military cooperation, an area that had formed the backbone of close ties between Britain and the US in the Bush era.

Officials said Brown would use the meeting to impress on Obama the need to put "greater pressure" on other European countries - apart from Britain - to commit more troops to Afghanistan.

Britain, which already has 8,300 troops in the volatile southern province of Helmand, has insisted that the Obama administration understood its position and had not asked for more British troops.

It was therefore not expected that Obama would "look to Britain first" when it came to increasing NATO troop levels in Afghanistan.

Brown, who will be accompanied by his wife, Sarah, will be in Washington at the same time as Tony Blair, his predecessor, who is attending a climate change conference in the US capital. dpa