Washington ? A Senate Republican who backs Northrop Grumman Corp.’s bid for a disputed $35 billion Air Force tanker contract wants to withhold funding until the service resolves a company gripe with the competition.

Sen. Jeff Sessions of Alabama filed an amendment Thursday that would require the Air Force to release pricing information of previous bids from both Northrop and its partner, Airbus parent European Aeronautic Defense and Space Co. NV, and rival Boeing Co.

The move follows reports that the Air Force may have disclosed price data about Northrop’s bid to Chicago-based Boeing during last year’s competition to replace the 179 aging tankers.

The Pentagon’s weapons buyer, Ashton Carter, has said the department found “no competitive disadvantage” following its examination of Northrop’s claim.