As the momentum for upcoming G-20 Summit in London gains ground, the White House has said that world should act together to prevent reoccurrence of the global economic downturn being experienced now.

US President Barack Obama would be trying to emphasise for global effort to avoid a repeat of economic crisis during his meetings with the world leaders at the G-20 summit, White House spokesperson, Robert Gibbs said on Thursday.

"The President will talk to other nations of the G-20 about acting together in hopes of doing the same without, negotiating some specific commitment," he told reporters at his daily press briefing.

Two European countries � France and Germany � has already opposed the idea of a stimulus packages in their countries.

The French President, Nicolas Sarkozy, said Europe has already invested a lot for the recovery and that the problem is not about spending more, but putting into place a system of regulations so that the economic and financial catastrophe.

"I think we're going to talk to other countries and other nations about continuing to do what's necessary to get through this crisis. But again, this isn't -- I also think it's important that we not think of this event as just simply one moment in time," Gibbs said.

"Obviously once we're done with the summit, people are going to have to evaluate both where their economies are and where the global economy is, and make changes," he said.

As such Obama looks forward to talking to leaders about a shared agenda to manage the crisis that the world is in and to also prevent a future crisis from happening.

"I think the summit will also speak about what we can do through international institutions to ensure that emerging economies either in the developing world or in places like Eastern Europe don't suffer catastrophically from either a burdening of their financial systems or a great change in world demand for exports and trade," Gibbs said.