WASHINGTON — Senior Trump administration and military officials are recommending sending several thousand additional American troops to Afghanistan to try to break a military deadlock in the 15-year war there, in part by pressuring the Taliban to negotiate with the Afghan government.

The added troops would allow American advisers to work with a greater number of Afghan forces, and closer to the front lines.

The recommendation, which has yet to be approved by President Trump, is the product of a broad review by the Pentagon, the State Department, intelligence community and other government agencies on America’s longest war. It is broadly consistent with advice Gen. John W. Nicholson, the top American commander in Afghanistan, gave Congress in February.

Warning that the United States and its NATO allies faced a “stalemate,” General Nicholson told lawmakers that he had a shortfall of a “few thousand” troops and said more personnel would enable the American military to advise the Afghan military more effectively and at lower levels in the chain of command.