The White House will soon ask Congress for emergency funds to fight the coronavirus outbreak, after weeks of hesitation by the administration to press for additional funding, said four individuals with knowledge of the pending request.

However, the amount could be significantly lower than some public health officials have argued is necessary — potentially as little as $1 billion, said two individuals, which could be rapidly exhausted by development of potential vaccines, widespread lab tests and numerous other investments.

A White House official told POLITICO that the pending request is still preliminary and the sum could change. A congressional aide said that lawmakers have been told to expect the request in the coming days.