Washington (CNN) A lobbying firm backed by Saudi Arabia booked hundreds of rooms at the Trump International Hotel in Washington shortly after the 2016 election, The Washington Post reported Wednesday.

The firm, Qorvis/MSLGroup, "has long represented the Saudi government in the United States," according to the Post. The group booked nearly 500 nights at the hotel to house US military veterans who were invited to DC to lobby against a law the Saudis opposed, the Post said, citing veterans and organizers of the trips.

"In all, the lobbyists spent more than $270,000 to house six groups of visiting veterans at the Trump hotel, which Trump still owns," the paper said. Although the bill for the rooms was footed by the Saudis, only American veterans stayed in them during trips in December 2016 and January and February 2017, according to the paper.

The Post reported that veterans were recruited to lobby lawmakers against the Justice Against Sponsors of Terrorism Act, which "opened the door to costly litigation alleging that the Saudi government bore some blame" for the September 11, 2001, terrorist attacks. Some of the veterans, according to the paper, didn't know they were staying in rooms paid for by the Saudis.

"It made all the sense in the world, when we found out that the Saudis had paid for it," Henry Garcia, a Navy veteran from Texas who went on several of the trips, told the paper.

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