Iranian Foreign Minister Mohammad Javad Zarif said on Monday that Iran is ready for further swap of prisoners with the United States.

"After getting our hostage back this week, we are fully ready for comprehensive prisoner exchange," Zarif tweeted.

Now, "the ball is in the U.S. court," Zarif said in Turkey's Istanbul, where he joined the ministerial conference of Heart of Asia Istanbul Process for peace and development in Afghanistan.

The remarks by the Iranian foreign minister followed Saturday's exchange of two prisoners between Tehran and Washington, a detained American on spying charges for an imprisoned Iranian researcher for violating sanctions on Iran.