Richard Boucher, the U.S. assistant secretary of state for South and Central Asian affairs, told reporters after the meeting that his discussions had focused on regional U.S. energy projects and the upcoming Tajik presidential election.
He added that Washington thinks "this election can be a step forward in terms of meeting international standards, and also building the practices and institutions that will serve Tajikistan well for democratic stability in the future."
Boucher later met with opposition leaders and representatives of nongovernmental organizations at the U.S. Embassy in Dushanbe.
Among those in attendance were Rahmatullo Valiev, the acting chairman of the Democrat Party, and Socialist Party leader Mirhuseyn Nazriev.
RFE/RL's Tajik Service reports the leaders of the rival Democratic and Socialist parties that have been coopted by the government were not present.
Six candidates have announced their intention to run in the November 6 election, including Rakhmonov, who is seeking a third term. Rakhmonov has been in office since 1992.
Besides Rakhmonov, only one candidate has been officially registered.