The US Defense Secretary has arrived in Kabul to look at the future of the US military in Afghanistan.
During his visit, Mark Esper will meet the country's President, Ashraf Ghani and US troops in the country.
He told reporters travelling with him: "The aim is to still get a peace agreement at some point."
Peace talks with the Taliban have stalled, and persistent violent attacks by the insurgent group and so-called Islamic State have complicated the Trump administration's pledge to withdraw more than 5,000 American troops.
Mr Esper told reporters he believes the US can reduce its force in Afghanistan to 8,600 without hurting the counter-terrorism fight against al-Qaeda and IS.
But he said any withdrawal would happen as part of a peace agreement with the Taliban.
The US has about 14,000 troops in Afghanistan as part of the US-led coalition, training and advising the Afghan forces and conducting counter-terrorism operations against insurgents.
President Donald Trump had ordered a troop withdrawal in conjunction with the peace talks that would have left about 8,600 American forces in the country.
US envoy Zalmay Khalilzad had a preliminary peace deal with the Taliban, but a surge in Taliban violence and the death of an American soldier last month prompted Mr Trump to cancel a secret Camp David meeting where the peace deal would have been finalised.
He declared the tentative agreement dead.
Mr Esper's arrival in Kabul came as Afghan government leaders delayed the planned announcement of preliminary results of last month's presidential election.