WASHINGTON - British Prime Minister David Cameron will tell leaders of some of the world's biggest economies on Friday that they must work together to stop the economic crisis afflicting the euro zone from spreading worldwide.

Cameron's message to other Group of Eight leaders, who begin a summit on Friday at the US presidential retreat of Camp David, Maryland, would be that "we need to work together to protect ourselves against global contagion from the economic crisis and to promote global trade," an aide to Cameron said.  

Clearly worried about the impact that the deteriorating euro zone situation and possibility of a Greek default could have on the weak British economy, Cameron has been increasingly vocal in urging Europe's rulers to do more to quell the debt crisis.

Cameron, whose poll ratings have plunged at home as the British economy has slid back into recession, will push at the G8 for a "strong and united commitment to securing the economic recovery and to support job creation," the aide said.

Cameron will speak out against protectionism and appeal for a trade liberalization drive to try boost the world economy.

In an article published on Friday, Cameron called for negotiations on an ambitious US-European Union trade agreement to begin next year.

"Together, the EU and US account for almost a third of global trade, so a deal with the US could potentially be bigger than all the other EU trade deals on the table," Cameron wrote in an opinion piece for PoliticsHome, a political website.

"With families across the world struggling with the impact of oil prices and a fragile global economy, we must renew our joint efforts to support growth, financial stability and energy security," he wrote.

Oil Market

His reference to oil prices may be significant because there have been reports that US President Barack Obama will seek support from other G8 leaders at this weekend's summit to tap emergency oil reserves.

The leaders will discuss the oil market at the summit, but a British government source said no announcement was expected.

Before the G8 summit starts, Cameron will have his first meeting with new French President Francois Hollande in Washington, when they are expected to discuss how they can work together on a package of measures to stimulate growth across Europe, the aide to Cameron said.

Hollande has vowed to shift Europe's focus to growth, while Cameron, a center-right Conservative who leads a two-year-old coalition government, has tended to side with German Chancellor Angela Merkel in stressing the importance of cutting debt.

Cameron, who refused to meet Hollande when the French Socialist visited London in February during his election campaign, will also discuss Afghanistan, Iran, Syria and Anglo-French defense cooperation with Hollande.

Despite his calls for determined efforts to "secure the economic recovery," Cameron has resisted pressure from his political opponents to spend more to lift growth at home.

He insists he must stick with unpopular austerity measures to rein in Britain's big budget deficit and retain credibility with the markets.