Asking industrialised nations to avoid protectionism in the trade of goods and services, Prime Minister Manmohan Singh said on Tuesday it was important and necessary for the G-20 Summit to take 'credible decisions' to help reverse the current slowdown and instil a confidence in the global economy.

In a statement before leaving for London to participate in the meeting of world leaders to discuss the economic meltdown, Singh also focussed on the need to ensure adequate flows of finances to the developing countries to overcome the reversal of international capital flows.

Singh, who will have his maiden meeting with US President Barack Obama on Thursday, said the time has come for the international economic and financial architecture to reflect contemporary economic strengths.

The prime minister, who is undertaking his first trip abroad after the coronary bypass surgery on January 24, said considerable amount of preparation has been done for the summit.

These preparations relate to provision of coordinated fiscal stimulus by major economies to offset the decline in private demand, agreement on a set of principles to plug loopholes and weaknesses in the supervisory and regulatory arrangements for the financial institutions, he said.

He underlined the need to undertake effective measures designed to provide emerging and developing countries adequate resources to offset the effects of global slowdown on their economies.

"It is important and necessary for the summit to take credible decisions which will help to halt and reverse the current slowdown and to instill a sense of confidence in the global economy," he stressed.

"It is an unfortunate reality that the effects of the slowdown have spread across the world, and developing countries, particularly those in Africa, are facing its worst consequences," the prime minister said.

He asked the developed countries to steer clear of protectionism and work towards restructuring and reforming the international financial institutions.