The UN nuclear watchdog says it will need more money to ho help pay for its monitoring mission in Iran.
The International Atomic Energy Agency (IAEA) has been monitoring a preliminary agreement between Iran and six world powers.
That deal has now been extended after Iran and the United States, France, Germany, Britain, and Russia failed to meet a November 24 deadline to secure a comprehensive deal.
Instead, the sides have given themselves until the end of June for further negotiations.
Under the preliminary deal, Iran halted its most sensitive nuclear activity in exchange for limited sanctions easing.
Iran denies it is secretly developing a nuclear weapons program as the West suspects.
Under the preliminary deal, IAEA inspectors now visit Iran's uranium-enrichment facilities of Natanz and Fordow daily, compared to about once a week before.
The IAEA did not say how much more money it would need.
Based on reporting by Reuters