New documents show Steve Bannon (above) hoped to 'leverage' Kushner's alleged vacation with a Russian billionaire

A tranche of newly released documents from Special Counsel Robert Mueller's investigation have revealed that Jared Kushner and Ivanka Trump took a vacation in Croatia with a mystery 'Russian billionaire' during the 2016 campaign.

Also on the trip was and Rupert Murdoch's former wife Wendi Deng.

According to the notes, former White House Chief Strategist Steve Bannon raised questions about the vacation and found it so dubious that he planned to 'leverage' the meetup with the Russian against Donald's Trump's son-in-law, Jared.

The documents, including 274 pages of Mueller team interview notes, emails and other documents related to the investigation, were released on Saturday in response to a lawsuit from CNN and Buzzfeed.

'Bannon knew Kushner was on vacation off the coast of Croatia with a Russian Billionaire when Bannon took over the campaign,' a summary of an investigative interview with Bannon read.

The summary said that Kushner was with Deng, the Russian billionaire, and the Russian's girlfriend, but it does not name the Russian.

Kushner and Ivanka Trump spent the Croatia vacation (above) aboard the megayacht of billionaire Democrat donor David Geffen

The couple was seen jet skiing in Croatia off the $200million boat

The documents included this summary of DOJ investigators' interview with Steve Bannon

Bannon told friends in the intelligence community that he thought Kushner's choice of vacation company was 'questionable,' according to the interview summary.

Kushner's and Ivanka Trump's vacation in August 2016 was previously documented in photos obtained by DailyMail.com, but the presence of a Russian billionaire had not been reported.

Throughout the trip, Deng was photographed with Kushner and his wife Ivanka.

In an email dated July 24, 2017 to an individual with a Breitbart domain email, Bannon referenced Kushner's vacation and appeared to indicate that the information, if reported and confirmed, could be valuable against Kushner.

Bannon was widely known to be in a bitter power struggle with Kushner and Ivanka while serving in the White House, reportedly referring to the couple as the 'New York globalists.'

'He was on 'vacation' off the coast of Croatia with a Russian billionaire when I took over the campaign,' Bannon wrote to the Breitbart employee, whose name was redacted in the released documents.

Kushner and Ivanka (left) went sightseeing in Dubrovnik with Wendi Deng (right with Ivanka)

This email chain dated July 24, 2017 was part of the released documents

'How do we prove that?' the Breitbart employee replied. 'That's game set match.'

Kushner and Ivanka Trump spent the Croatia vacation aboard the megayacht of billionaire Democrat donor David Geffen.

David Geffen, who was one of the earliest supporters of Barack Obama and donated to both Hillary Clinton and Bernie Sanders in the 2016 primary, hosted Kushner and Ivanka Trump on his boat the Rising Sun.

The couple was seen jet skiing in Croatia off the $200million boat, and later went sightseeing in Dubrovnik with Wendi Deng and Brian Grazer and his new wife Veronica.