Afghan President Ashraf Ghani has offered to negotiate ways to minimize the costs of keeping U.S. troops in Afghanistan amid concern that U.S. forces will pull out of the region prematurely, a new report says.

Although Ghani did not include specific proposals for how to cut costs of U.S. troops and contractors in Afghanistan, his letter to President Trump dated Monday says the objective is “maximum effectiveness to aid efficiency.” He also requested Trump visit Afghanistan soon to “discuss a mutually beneficial path forward toward lasting peace and increased security for both of our countries and peoples,” the Wall Street Journal reports.

Ghani also alluded to media reports that Trump instructed the Pentagon to withdraw half of the roughly 14,000 U.S. troops in Afghanistan in December, although the National Security Council denied that such orders were given.

“While the Afghan government remains a steadfast and committed partner to the United States in the pursuit of our shared security and peace objectives, we are aware of the recent changes in the context of our relationships and a seeming shift in U.S. priorities and objectives in our country and the region,” Ghani wrote in the letter.

Although it was uncertain as of Thursday if Trump had received the correspondence, the letter comes after U.S. Special Representative for Afghanistan Reconciliation Zalmay Khalilzad met with the Taliban in Qatar last week.

Khalilzad said over the weekend that discussions with the Taliban in Qatar were “ more productive than they have been in the past” and that the U.S. and Taliban agreed on a draft framework that would pull out the U.S. troops from Afghanistan in the future, one of the Taliban’s top priorities.

[Read more: US withdrawal from Afghanistan requires Kabul government and Taliban to strike peace deal first]

Ghani has reportedly grown irritated that the Afghan government has been shuttered from the discussions with the Taliban, who have resisted negotiating with the Afghan government, and has said that such negotiations should be “Afghan-led and Afghan-owned.”

Meanwhile, acting Secretary of Defense Patrick Shanahan said Tuesday that the discussions between the U.S. and the Taliban were encouraging and that he has not been instructed to develop plans for a U.S. withdrawal at this point.

The U.S. Inspector General for Afghanistan Reconstruction claims the U.S. has provided more than $132 billion for Afghanistan’s reconstruction and estimates that up to $800 billion has been spent on the war there.