Rick Gates: Who is he, why has he been arrested, and what is his connection to Trump and Russia?

Mr Gates joined Mr Manafort's lobbying office in 2006

Mr Gates faces several federal charges stemming from the federal investigation into Russia's 2016 election meddling (AP)

Richard "Rick" Gates, a business partner of Paul Manafort and former Donald Trump campaign official, has been indicted by special counsel Robert Mueller on federal charges stemming from alleged financial ties to Russian-connected sources.

Up until now, Mr Gates has been a little-known player in the Trump orbit, having joined the campaign after Mr Manafort was elevated to being his campaign manager, serving as his deputy. Mr Gates would end up continuing to serve Mr Trump even after his business partner was fired from the campaign, serving as a liaison for the campaign with the Republican National Committee, and later helping to plan the incoming president’s inauguration.

Mr Gates has been charged, alongside Mr Manafort, on 12 federal charges, including conspiracy against the United States, conspiracy to launder money, unregistered agent of a foreign principal, false and misleading US Foreign Agents Registration Act statements, false statements, and seven counts of failure to file reports of foreign bank and financial accounts. Mr Mueller's team has investigating Russia's meddling in the 2016 election, and whether Trump campaign officials colluded in the effort.

Both Mr Gates and Mr Manafort pleaded not guilty in federal court to their alleged crimes.

Mr Gates met Mr Manafort nearly two decades ago, when he first interned at the consulting firm Black, Manafort, Stone, Kelly. He apparently stayed in touch, and officially joined Mr Manafort’s lobbying firm, Davis Manafort, in 2006.

The two reportedly had several clients with connections to the Kremlin, including the Russian oligarch Oleg Deripaksa, who was a client. That relationship soured when Mr Deripaska claimed that Mr Gates and Mr Manafort made off with about $19 million of his money.

Their relationship with individuals in Vladimir Putin’s orbit did not end there, however. The two would later work for former Ukrainian President Viktor Yanukovych, in 2014. That involvement came in spite of opposition to Mr Yanukovych from the US government.

After helping with the Trump campaign’s inauguration planning, Mr Gates ultimately left to work for America First Priorities, a pro-Trump group. He left that job after a few months.

Mr Gates and Mr Manafort surrendered Monday morning, and were scheduled to appear in federal court later that day.