American Ethane touts a contract it signed with the Nanshan Group , an aluminum production company based in China. The development also comes as the Trump administration is engaged in high-stakes trade talks with the Chinese government.

The document shows that Osborne and Ryan O'Dwyer, who previously was a special assistant to the secretary of Agriculture and a senior public liaison to Trump's inaugural committee, will be the lobbyists representing American Ethane on trade and energy issues.

Turnberry Solutions, a lobbying group run by former Trump campaign advisor Jason Osborne, has signed American Ethane as a client, according to a new lobbying disclosure form. The filing was posted on the Senate lobbying disclosure website on Tuesday.

A lobbying firm run by former advisors to President Donald Trump is representing American Ethane Company, an energy producer funded by Russian billionaires that is involved with a Chinese aluminum company.

"Ryan O'Dwyer and I were hired to help a U.S. company get permits issued to them to fulfill a contract signed during a signing ceremony between President Trump and President Xi," Osborne told CNBC. The deal was signed at a ceremony in November 2017 in front of Trump and China's president, Xi Jinping.

Osborne also said their work entails getting members of Congress in Louisiana and Texas to submit official inquiries through the U.S. government and the Chinese government in the hopes their contract would be honored.

Turnberry also touts former Trump campaign manager Corey Lewandowski and onetime Secretary of the Interior Ryan Zinke as senior advisors. Zinke resigned from the administration last year amid numerous ethics investigations and complaints, while Lewandowski has reportedly continued to advise Trump from an outside position.

The filing lays out the top two foreign investors backing the ethane producer. Konstantin Nikolaev, a Russian billionaire with an estimated net worth of $1.2 billion, is listed as an investor with a 30 percent stake in the company.

According to Forbes, Nikolaev and his business partners own a 34 percent stake in Globaltrans, Russia's biggest private rail transport operator. Another financier is Andrey Kunatbaev, a Russian billionaire who helped start TV-3, a Russian entertainment channel, according to American Ethane's website. Kunatbaev is also a member of the company's board, the website says.

It's unclear how much American Ethane is paying Turnberry for their lobbying services.

American Ethane CEO John Houghtaling did not return requests for comment.

Turnberry signed with the Russian-backed energy firm as the White House continues to be haunted by suspicions about the president and his associates' potential connections to the Kremlin. Trump has repeatedly denied colluding with the Russian government as part of efforts to interfere with the 2016 election.

Turnberry also lobbies for wireless company T-Mobile and energy management company Redhorse Corporation, among others.