The U.S. is closing in on a deal with the Taliban that is designed to wind down America’s 18-year war in Afghanistan, but the best indication of how risky the pact may be is this: Secretary of State Mike Pompeo is declining to sign it, according to senior U.S., Afghan and European officials.

The “agreement in principle” that U.S. envoy Zalmay Khalilzad has hammered out in nine rounds of talks with Taliban representatives in Qatar would take the first tentative steps toward peace since U.S. and allied forces deployed to Afghanistan following the attacks on 9/11, according to senior Afghan and Trump Administration officials familiar with its general terms. Defense Secretary Mark Esper was scheduled to discuss the closely held details of the deal with President Donald Trump in a Sept. 3 meeting, according to senior administration officials. If Trump approves and a deal is struck, it could begin a withdrawal of some 5,400 U.S. troops, roughly a third of the present force, from five bases within 135 days.

But the deal doesn’t ensure several crucial things, those familiar with the discussions tell TIME. It doesn’t guarantee the continued presence of U.S. counterterrorism forces to battle al Qaeda, the survival of the pro-U.S. government in Kabul, or even an end to the fighting in Afghanistan.