For the embattled Arab nation of Qatar, lobbyists with President Donald Trump’s ear are getting extremely expensive.

As the president seeks to calm tensions between Qatar and its Gulf neighbors, a lobbying firm representing the country, and founded by top former Trump campaign aides, is hiking its fees dramatically. Avenue Strategies is now pulling in an annualized $6 million for its advocacy on Qatar’s behalf.

The dramatic hike came just days before Trump arranged negotiations between Qatar and its regional adversaries. As the president remains involved in trying to sort out an ongoing diplomatic dispute, the ability to influence his thinking on major international matters is getting increasingly valuable—and pricey.

Avenue Strategies, co-founded by former Trump campaign manager Corey Lewandowski, who has since left the firm, and campaign adviser Barry Bennett, is benefiting handsomely from that dynamic. The firm boosted its monthly retainer fee from $150,000 to $500,000, the firm disclosed to the Department of Justice in a filing made public on Thursday.

Avenue inked its amended contract on September 5, three days before Trump arranged a phone call between leaders of Qatar and Saudi Arabia. The two countries have been locked in a diplomatic crisis since June 2017, when Saudi Arabia and other Arab nations cut ties with Qatar over its alleged support of terrorism in the region.

The Trump-arranged phone call between Saudi and Qatari leaders failed to quell the tension in the region. The president also met with Qatari emir Sheikh Tamim bin Hamad Al Thani during the meeting of the United Nations general assembly in New York on Tuesday.

“I have a very strong feeling that it will be solved pretty quickly," Trump said at the UN of the ongoing diplomatic row.

Trump’s tone on the dispute has softened since he flatly labeled Qatar a “funder of terrorism” in June, but he reportedly chided the emir at Tuesday’s meeting over the country’s continued involvement with U.S.-designated terrorist groups.

The president’s involvement in sorting out the dispute has fueled a proxy battle between the countries’ U.S. lobbying firms, who have vied for the president’s attention and favor between two key strategic partners in the Middle East—Saudi Arabia a longtime U.S. ally, and Qatar the host of America’s largest military base in the Gulf region.

Avenue Strategies leads that campaign for Qatar, and its ties to the president are deep. In addition to Bennett and Lewandowski, the firm has employed high-level Trump campaign operatives Mike Rubino and Jason Osborne. They recently split off to form a separate lobbying firm, Turnberry Solutions.

But the exorbitant fees that Qatar is willing to pay for Avenue’s services demonstrate the firm’s continued political heft. Its $500,000-per-month contract will last through the end of the year, according to the disclosure filings released by DOJ on Thursday.

Avenue and its Qatari client are facing an increasingly formidable lobbying presence on the other side of the Gulf diplomatic dispute. Saudi Arabia retains a host of U.S. lobbying firms, including some hired specifically for advocacy and public relations campaigns aimed at undercutting Qatar’s standing in the eyes of the Trump administration.

One of those firms, the Podesta Group, recently teamed up with a U.S.-based nonprofit group run by a Saudi national to produce ads echoing the Saudi government’s attacks on Qatar. The ads were run on cable news programs and at the British Open golf tournament—the latter placement chosen explicitly due to the president’s known interest in professional golf.

The Saudi-backing non-profit, dubbed the Saudi American Public Relations Affairs Committee, drew scrutiny for its failure to register as a foreign agent under U.S. law, a designation reserved for groups funded by or acting at the direction of a foreign government or political party. SAPRAC insists it is independent of the Saudi government.

But Avenue Strategies pounced. It filed a complaint with DOJ alleging that SAPRAC had failed to register as required under the Foreign Agents Registration Act. Days later, SAPRAC filed paperwork with DOJ disclosing a $1.2 million contract not with Saudi Arabia, but with the Kingdom of Bahrain, another leading Qatar adversary.

On Thursday, Bahrain disclosed a new foreign agent on its payroll: Washington-based political video firm CRAFT, which will receive $921,000 to produce and place ads for its client.