US says Islamic State conducted attack on Kabul hospital

But it was unclear if the US declaration would be enough to bolster the peace effort and reverse a decision by the Kabul government to resume offensive operations against the Taliban.

Afghan President Ashraf Ghani ordered the military on Tuesday to switch to "offensive mode" against the Taliban following the hospital attack in Kabul and a suicide bombing in Nangarhar province that killed scores of people.

US Special Representative Zalmay Khalilzad blamed Islamic State for both attacks in a statement issued on Twitter, saying the group opposed any Taliban peace agreement and sought to trigger an Iraq-style sectarian war in Afghanistan.

"Rather than falling into the ISIS trap and delay peace or create obstacles, Afghans must come together to crush this menace and pursue a historic peace opportunity," Khalilzad said.

"No more excuses. Afghans, and the world, deserve better."

An affiliate of the Islamic State terrorist group claimed responsibility for the Nangarhar bombing, according to the SITE Intelligence Group. No one has claimed the hospital attack.

The Taliban denied involvement in either attacks, but the government accused the group of fostering an environment in which terrorism thrives or of working with other terrorist groups who could have been involved, straining US efforts to bring the insurgents and Afghan government together.

The attacks were another setback to US President Donald Trump's stalled plans to bring peace to Afghanistan and end America's longest war.

A Feb. 29 US-Taliban deal called for a phased US troop withdrawal and for the Afghan government and Taliban to release some prisoners by March 10, when peace talks were to start.

Intra-Afghan peace talks have yet to occur and there is some bitterness within the Afghan government, which was not a party to the Feb. 29 deal, that the United States undercut their leverage by negotiating directly with the Taliban.