The top diplomats from the major industrialised nations held a previously scheduled meeting by videoconference, with the United States scrapping a meeting in Pittsburgh as the contagion fears restrict international travel.
Pompeo, who has heavily criticised Beijing over what he calls the "Wuhan virus," said he was united with other ministers - from Britain, Canada, France, Germany, Italy and Japan.
"Every one of the nations that were at that meeting this morning was deeply aware of the disinformation campaign that the Chinese Communist Party is engaged in to try and deflect from what has really taken place," Pompeo told reporters after the talks.
Pompeo said that China "has been and continues to be engaged in" a campaign on social media that has included conspiracy theories that the United States was behind the virus, which was first detected in the Chinese metropolis of Wuhan.
"This is crazy talk," Pompeo said.
The G7 talks came a day before a virtual summit of leaders of the Group of 20 major economies, which include the United States and China.
Beijing has appeared to bring the virus under control and has stepped up aid by delivering masks and other supplies around the world - including to US allies such as Italy, which has the world's highest death toll.
Pompeo minimised China's efforts and said the United States was "finalising plans" to deploy excess military equipment to Italy.
China is "now making small sales of product around the world and claiming that they are now the white hat in what has taken place," Pompeo said.
But he said the United States sought cooperation.
"We desperately want to work with every country around the world. This is a global pandemic," he said.
"The United States wants to work with every country including China to figure out how to resolve to keep as many people alive - as many people as healthy - and then to restore our economies that have been decimated by the Wuhan virus." (AFP)