US special counsel Robert Mueller has hit President Donald Trump’s former campaign manager with Paul Manafort with charges that he set up a secret lobbying campaign involving former senior European politicians.

Mueller has charged that Manafort secretly enlisted “former senior European politicians” in 2012 and 2013 to lobby on behalf of the government of former pro-Russian Ukrainian President Viktor Yanukovych, who fled the country for Moscow in February 2014 following the Euromaidan Revolution.

The Europeans – known as the “Hapsburg Group” in reference to the dynasty that ruled the Austro-Hungarian Empire – were led by a “former European chancellor” and allegedly covertly paid by Manafort.

Mueller’s charges state that Manafort and and his deputy Rick Gates “secretly retained the group of former senior European politicians to take positions favourable to Ukraine, including lobbying in the United States,” adding “The plan was for the former politicians to appear to be providing their independent assessments of the Government of Ukraine, when in fact they were paid lobbyists for Ukraine.”

According to Justice Department documents, the group was allegedly managed by “a former European chancellor” who is referred to on the charge sheet as “Foreign Politician A”. The documents indicate that the politician in question is former Austrian Chancellor Alfred Gusenbauer.

Gusenbauer has admitted that he accepted payments from either “an American or British company” to lobby on behalf of Ukraine under the Yanukovych regime, but could not recall which issues he was charged with addressing.  He has denied that he consciously took money from Manafort during either of their two meeting in undisclosed locations in the US and Europe.

Mueller has also accused both Manafort and Gates of setting up a Brussels thinktank known as the European Centre for Ukraine – which acted as a lobby for the Yanukovych regime and its pro-Russian policies.

The new indictment against Manafort was filed in US District Court in Washington just after Gates pled guilty to related charges. Gates pled guilty to conspiracy against the United States and lying to investigators, and is now cooperating with a federal probe into Russia’s role in the 2016 election.

Gates had been potentially facing decades in prison on much more serious charges, including bank fraud and conspiracy to launder money. Prosecutors said they could ask the judge for a reduction in Gates’ sentence based on the extent of his cooperation with Mueller’s probe.

The plea increases pressure on Manafort, who was Trump’s campaign manager for five months in 2016, to also seek a plea bargain. Manafort, however, said in a statement issued after Gates’ plea deal that he will continue to maintain his innocence.

Meanwhile, the Democratic Party has released a redacted memo challenging Republican claims that the FBI abused government surveillance powers in its investigation of Russia’s election meddling, a document Trump had previously blocked.

The House Democrats’ document, released on February 24, attempted to counter claims made in a previous Republican-written memo and focused on longstanding FBI concerns about Trump campaign aides’ links to Moscow.

Democrats say the FBI and Justice Department “did not abuse” procedures, “omit material information” or “subvert” government regulations in requesting court permission to conduct surveillance on a member of the Trump campaign team.

Republicans on the House Intelligence Committee released their memo on February 2 and accused the two law-enforcement organisations of being biased against Trump and of hiding information as part of the investigation into Russian meddling and the Kremlin’s links to the Trump team.

At least five people — including three former Trump aides — have pleaded guilty in special counsel Robert Mueller’s investigation, though the charges have been financially related and do not directly allege collusion with Russia. 13 Russians and three Russian companies have also been indicted in Mueller’s probe.