US Secretary of State Mike Pompeo on Monday demanded demonstrable evidence from the Taliban that it can and will reduce violence before signing a deal that would lead to Afghanistan peace talks and a withdrawal of American troops from the country.

Speaking at a news conference in neighboring Uzbekistan, Pompeo said a deal is close but that they have been close before and failed because the Taliban was unable to demonstrate its seriousness. He said more work remains to be done so that peace talks can get started.

We’re working on a peace and reconciliation plan, putting the commas in the right place, getting the sentences right, he said. We got close once before to having an agreement: a piece of paper that we mutually executed and the Taliban were unable to demonstrate either their will or capacity or both to deliver on a reduction in violence.

So, what we are demanding now is demonstrable evidence of their will and capacity to reduce violence, to take down the threat, so the inter-Afghan talks ... will have a less violent context, he said. We’re hopeful we can achieve that but we’re not there yet, and work certainly remains.

Pompeo’s comments came just two days after US peace envoy Zalmay Khalilzad arrived in Kabul and told Afghan President Ashraf Ghani there has been no notable progress in talks with the Taliban. However, Khalilzad said he was hopeful of reaching an understanding with them on a reduction of hostilities, without offering any time frame.

Former president Hamid Karzai, however, who also met with the US envoy, reported that Khalilzad expressed his optimism about the developments and progress in the peace process.

Khalilzad had been in Pakistan last week to rally support for getting an agreement with the Taliban to reduce their attacks, as a first step toward a peace agreement to end 18 years of war in neighboring Afghanistan.

He was appointed by the White House in 2018 to find a negotiated end to Afghanistan’s war that would allow the United States to bring home its estimated 13,000 soldiers and end its longest military engagement.

He has held multiple rounds of talks with the Taliban in the Mideastern state of Qatar where the militant group maintains a political office.

Talks in recent weeks have focused on finding a way to reduce hostilities and bring both sides in the conflict to the negotiating table. Until now the Taliban have refused to talk to Afghan President Ghani’s government.

Ghani has also been unable to agree on a negotiating team with Abdullah Abdullah who is currently his partner in Afghanistan’s so-called Unity Government. Abdullah accuses the president of foiling efforts at peace by imposing new conditions on talks.

Ghani and Abdullah were the leading contenders in last September’s presidential polls. The voting was mired in controversy and is still without a final result.