Iran has hosted the political leader of Afghanistan's Taliban during the past week, offering Tehran's own help as a mediator in peace talks between the insurgents and the Afghan government that have become stalled in Qatar.
Shi'ite Muslim Iran has been a foe of the hardline Sunni Muslim Taliban for decades, but has been openly meeting with Taliban leaders for the past few years as the United States has started negotiating the exit of its troops from Afghanistan.
Washington has accused Iran in the past of providing covert aid to Taliban fighters against U.S. forces.
Iran's Foreign Minister Mohammad Javad Zarif met Taliban political chief Mullah Abdul Ghani Baradar in Tehran, and told him that Washington was not a "good mediator" for the conflict, Iran's Tasnim news agency reported on Sunday.
Iran supports an inclusive Afghan government that would include all ethnic groups and sects, Zarif was quoted as saying.
Taliban spokesman Mohammad Naeem said on Twitter that the meetings had taken place "in a good atmosphere".
"The situations in Afghanistan, Intra-Afghan negotiations, the full implementation of the Doha agreement and Afghanistan's & region's need (for) peace were discussed," he added.
The United States reached an agreement last year with the insurgents at negotiations in the Qatari capital to withdraw troops that have been in Afghanistan since 2001.
More recently, the Taliban and the Afghan government have been negotiating in Qatar to reach a peace deal. Those talks resumed this month after an almost month-long break, but negotiators and diplomats say there has since been little progress.
Reuters reported on Sunday that some NATO troops are likely to stay in Afghanistan beyond the deadline set last year of May 2021, as the Western alliance does not believe the withdrawal conditions have been met.
New U.S. President Joe Biden is expected to take a close look at the withdrawal agreement negotiated under his predecessor Donald Trump.