German Chancellor Angela Merkel and U.K. Prime Minister Gordon Brown Thursday called on Russia and the Ukraine to start negotiations again and resolve their gas dispute.

German Chancellor Angela Merkel and U.K. Prime Minister Gordon Brown Thursday called on Russia and the Ukraine to start negotiations again and resolve their gas dispute.

Speaking to reporters after bilateral talks here, Merkel said there's the risk that Russia will lose trust due to the current gas dispute with the Ukraine which has also disrupted gas deliveries to Europe.

"I think there is the risk that confidence in Russia could be lost in the long term," Merkel told reporters. She added she will address the issue with Russian Prime Minister Vladimir Putin in talks Friday in Berlin.

The incidences of the past weeks are quite severe," Merkel said.

"It is our joint demand that we here in Europe will get again gas deliveries and call on Russia as well as the Ukraine to create conditions for this," she added.

Brown said that Europe must act together in a bid to help solve the gas dispute.

Both leaders also said the global financial system needs to be reformed in the wake of the financial market crisis.

"What we've discovered in this international financial crisis is that the institutions that were built for the age of the 1940s and 50s and 60s are no longer adequate for the problems of 2009," Brown said, adding that this also applied to climate change and energy security issues.

"There will have to be a better international architecture for the future...I believe the future international economic architecture will be one of the things that people will want to discuss at the G20 in April and I believe that if the world is going to solve problems that are global we need to have coordination that is global as well."

Leaders of the Group of 20 nations are due to meet in London April 2.

He said he "welcomes" Merkel's proposal on reforming the global financial system.

Merkel has proposed that the United Nations could serve as a forum for creating a new international regulatory framework by setting up a council that would have a different role from the U.N.'s Economic and Social Council, or ECOSOC.

She also said the government's stimulus plans will help to boost the economy, which is widely feared to be in it's worst recession in six decades. The German cabinet Wednesday provisionally approved an additional EUR50 billion stimulus program for 2009-2010, which comes after a EUR31 billion package adopted in November. These combined measures worth around EUR80 billion amount to 1.5% of gross domestic product.