An international panel is ready to investigate the deadly US bombing of a Médecins sans Frontières (MSF) field hospital in Afghanistan, the group said on Wednesday.

But before the investigation into potential US war crimes can begin, the International Humanitarian Fact Finding Committee (IHFFC) requires assurances from Barack Obama and the Afghan president, Ashraf Ghani, that their governments will comply.

The prospect of a war crimes inquiry raises the political stakes for Obama significantly: assenting to the investigation would be likely to trigger domestic political backlash, while obstructing it would leave the US open to accusations that it is covering up an incident which MSF has called an attack on the law of war itself.

The White House was noncommittal on Wednesday but signaled it was unpersuaded by MSF's claims that an independent inquiry is necessary.

"We have received apologies and condolences, but this is not enough," Joanne Liu, the international president of MSF, said in a Wednesday statement.