The new Trump International Hotel has been at the hub of conflict of interest charges directed at Trump because it is situated in a taxpayer-owned architectural gem, the Old Post Office, which Trump’s company leases from the federal government. But the agency that leased the property to Trump, the General Services Administration, told lawmakers that the lease forbids any elected official from holding the lease, the lawmakers said in a letter addressed to the agency’s administrator.

If Trump refused to give up the hotel after his inauguration next month, the GSA would typically drag him before an obscure, independent tribunal that oversees disputes involving federal agencies, the letter said. It said Trump’s team has not responded to the agency’s communications about the matter.

The letter, signed by four Democratic lawmakers, comes amid intense debate about how Trump’s business ties could conflict with his duties as President. The hotel, located just a few blocks from the White House, has drawn scrutiny as foreign diplomats and others interested in influencing the government stayed or planned events there in the weeks since Trump’s victory on November 8. Critics say that once Trump is president, he would be able to fire the head of the GSA, effectively making him both landlord and tenant — a classic conflict of interest.