Senators on both sides of the aisle on Monday expressed concerns about a report by CBS News that Pakistan had sheltered multiple Iranian military aircraft at an air force base in the country since shortly after the U.S.-Iran ceasefire in April, raising questions about the country’s neutrality as a meditator.

Sen. Lindsey Graham (R-SC) said the U.S. may need to reassess whether Pakistan, which helped broker the recent U.S.-Iran ceasefire deal, can continue to serve as a mediator between the warring parties.

“If this reporting is accurate, it would require a complete reevaluation of the role Pakistan is playing as mediator between Iran, the United States and other parties,” Graham said on X. “Given some of the prior statements by Pakistani defense officials towards Israel, I would not be shocked if this were true.”

Sen. Roger Wicker (R-MS), the chairman of the Senate Armed Services Committee, told Jewish Insider that the report is “not good news,” adding, “I don’t think there will be any more negotiations taking place in Pakistan.”

Sen. Mark Kelly (D-AZ) said he’d seen the CBS report and suggested it raised questions about Pakistan’s neutrality.

“Does that make you neutral? Not as neutral as we would like,” Kelly said. “I do think there needs to be somebody, some country in the middle, that has a stake in this.”

Sen. Ted Budd (R-NC) said that the report raises concerns for him about Pakistan’s neutrality as an arbiter in the talks as well.

The report comes as Pakistan is making moves to assert itself as a regional leader, signing a defense pact with Saudi Arabia and working toward one with Qatar, as well as building ties with Egypt and Turkey.

Islamabad also worked to support Iran’s economy during the war, despite U.S. sanctions and financial pressure.

Pakistan’s role as a mediator raised some questions on Capitol Hill, but other lawmakers have viewed Islamabad as a potentially productive partner — at a time when few other mediators were available.