The U.S. is pushing UN nuclear inspectors to check military sites in Iran, but for this to happen, inspectors must believe such checks are necessary and so far they do not, officials say.

“We’re not going to visit a military site like Parchin just to send a political signal,” Reuters quoted an IAEA official as saying, mentioning a military site often cited by opponents of the deal including Iran’s arch-adversary Israel and many U.S. Republicans.

Last week, U.S. Ambassador to the United Nations Nikki Haley visited the International Atomic Energy Agency, which is scrutinizing compliance with the 2015 agreement, as part of a review of the pact by the administration of President Donald Trump.

The IAEA has the authority to request access to facilities in Iran, including military ones, if there are new and credible indications of banned nuclear activities there, according to officials from the agency and signatories to the deal.

But they said Washington has not provided such indications to back up its pressure on the IAEA to make such a request.

IAEA Director-General Yukiya Amano frequently describes his Vienna-based agency as a technical rather than a political one, underscoring the need for its work to be based on facts alone.