Many world leaders have condemned a decision this week by U.S. President Donald Trump to suspend funding for the agency amid a crisis that has left more than 2 million people infected and almost 140,000 dead worldwide.
Merkel told a video conference of leaders of the Group of Seven (G7) industrialised nations that the crisis can only be tackled with a strong and coordinated international response.
And the German leader expressed her full support for the WHO in the call, her spokesman Steffen Seibert said in a statement.
Merkel had also backed European Commission proposals for a virtual donor conference and said G7 countries had a special responsibility to help countries in Africa.
The United States contributed more than $400 million to the WHO in 2019, but Trump has accused it of promoting Chinese “disinformation” about the virus.
German Foreign Minister Heiko Maas, who hosted a video conference of foreign ministers in the Alliance for Multilateralism, a group of 23 countries, said the WHO remained the “backbone of the fight against the pandemic”.
“It makes no sense now to question the ability of the WHO to function or its significance,” he said after the talks, and that the Alliance had agreed to strengthen the body, adding there may be lessons to be learned once the worst of the crisis was over.
Asked if Germany would step in to help fill the gap left by the United States, Maas told reporters that jumping in when another country withdraws contributions was wrong in principle as it can encourage others to do the same.
Maas also said the Alliance, set up by Germany and France in 2018 to support the United Nations, agreed that ensuring a fair distribution of protective materials, tests and medicine as soon as they are available to poorer nations was needed.