Ousted White House chief strategist Steve Bannon is gearing up for battle and has set his sights on President Donald Trump's son-in-law and senior adviser, Jared Kushner, according to Vanity Fair.

Bannon and Kushner have a long history of disagreement, with the two frequently butting heads on the ideological plane, where Bannon's far-right nationalist instincts clashed with Kushner's more moderate views.

In the wake of his ouster, Bannon is looking to even the score with West Wing rivals like Kushner, Vanity Fair reported. In keeping with that, Bannon reportedly wants former chief of staff Reince Priebus to testify to special counsel Robert Mueller that Kushner was significantly involved in Trump's decision to fire former FBI director James Comey in May.

RELATED: Bannon in his White House role



17 PHOTOS Steve Bannon See Gallery Steve Bannon White House Chief Strategist Stephen Bannon speaks with White House chief of staff Reince Priebus before Japanese Prime Minister Shinzo Abe and U.S. President Donald Trump arrive for their joint news conference at the White House in Washington, U.S., February 10, 2017. REUTERS/Joshua Roberts White House Chief Strategist Steve Bannon and White House Director of Strategic Communications Hope Hicks walk along the colonnade ahead of a joint press conference by Japanese Prime Minister Shinzo Abe and U.S. President Donald Trump at the White House in Washington, U.S., February 10, 2017. REUTERS/Jim Bourg U.S. National Security Advisor Michael Flynn (R) and Senior Counselor Steve Bannon board Air Force One at West Palm Beach International airport in West Palm Beach, Florida U.S., February 12, 2017. REUTERS/Carlos Barria U.S. President Donald Trump's chief strategist Steve Bannon (L) and senior aide Kellyanne Conway speak at meeting hosted by Trump with cyber security experts in the Roosevelt Room of the White House in Washington January 31, 2017. REUTERS/Kevin Lamarque FILE PHOTO: Chief White House strategist Steve Bannon (L) sits with Chief of Staff Reince Priebus (C) and senior advisor Stephen Miller during a swearing-in ceremony at the White House in Washington, U.S., January 22, 2017. REUTERS/Carlos Barria U.S. President Donald Trump (L-R), joined by Chief of Staff Reince Priebus, Vice President Mike Pence, senior advisor Steve Bannon, Communications Director Sean Spicer and National Security Advisor Michael Flynn, speaks by phone with Russia's President Vladimir Putin in the Oval Office at the White House in Washington, U.S. January 28, 2017. REUTERS/Jonathan Ernst TPX IMAGES OF THE DAY U.S. President Donald Trump signs a memorandum to security services directing them to defeat the Islamic State in the Oval Office at the White House in Washington, U.S. January 28, 2017. Pictured with him are White House senior advisor Steve Bannon (L-R), National Economic Council Director Gary Cohn, Vice President Mike Pence, Deputy National Security Advisor K. T. McFarland, National Security Advisor Michael Flynn, National Security Council Chief of Staff Keith Kellogg and senior advisor Kellyanne Conway. REUTERS/Jonathan Ernst TPX IMAGES OF THE DAY Steve Bannon, Chief Strategist for US President-elect Donald Trump, talks on the phone outside Trump Tower in New York on December 9, 2016. (DOMINICK REUTER/AFP/Getty Images) U.S. President-elect Donald Trump (R) and senior counselor Steve Bannon (L) hold meetings at the Mar-a-lago Club in Palm Beach, Florida, U.S. December 28, 2016. (REUTERS/Jonathan Ernst) Republican presidential nominee Donald Trump's campaign CEO Steve Bannon is pictured backstage during a campaign event in Eau Claire, Wisconsin U.S. November 1, 2016. (REUTERS/Carlo Allegri) Republican presidential nominee Donald Trump's campaign CEO Steve Bannon (R) is pictured talking to a reporter after a campaign event in Phoenix, Arizona, U.S. October 29, 2016. (REUTERS/Carlo Allegr's) Republican presidential nominee Donald Trump's campaign CEO Steve Bannon holds a campaign rally the Reno-Sparks Convention Center November 5, 2016 in Reno, Nevada. With less than a week before Election Day in the United States, Trump and his opponent, Democratic presidential nominee Hillary Clinton, are campaigning in key battleground states that each must win to take the White House. (Photo by Chip Somodevilla/Getty Images) Republican presidential nominee Donald Trump's campaign CEO Steve Bannon (C) listens to Trump speak during his final campaign rally on Election Day in the Devos Place November 8, 2016 in Grand Rapids, Michigan. Trump's marathon last day of campaigning stretched past midnight and into Election Day. (Photo by Chip Somodevilla/Getty Images) Steve Bannon gets off the plane with US President-elect Donald Trump arrives at Cincinnati/Northern Kentucky International Airport in Hebron, Kentucky, for the start of the 'USA Thank You Tour' at the US Bank Arena in Cincinnati, Ohio, December 1, 2016. (TIMOTHY A. CLARY/AFP/Getty Images) Steve Bannon, chief strategist for Donal Trump, leaves after the motorcade of US President-elect arrived at Trump Tower on December 10, 2016 in New York. (EDUARDO MUNOZ ALVAREZ/AFP/Getty Images) Steve Bannon, (L) chief strategist for Donal Trump, exits Trump Tower on December 13, 2016 in New York. (EDUARDO MUNOZ ALVAREZ/AFP/Getty Images) Steve Bannon, senior counselor to U.S. President-elect Donald Trump, arrives to attend meetings between Trump and business leaders at the Mar-a-lago Club in Palm Beach, Florida, U.S. December 28, 2016. (REUTERS/Jonathan Ernst) Up Next See Gallery Discover More Like This HIDE CAPTION SHOW CAPTION of SEE ALL BACK TO SLIDE

According to Vanity Fair, Priebus believes Kushner and his wife, Ivanka, convinced Trump to fire Comey during a weekend they spent with the president at his golf club in Bedminster, New Jersey. When Trump returned to the White House on May 8, he informed aides that he was going to fire Comey, and he dismissed the FBI director the next day.

Comey's firing drew wide condemnation, and as accusations that Trump had fired Comey to obstruct an ongoing FBI counterintelligence investigation into whether his campaign colluded with Moscow in 2016 began piling up, deputy attorney general Rod Rosenstein appointed Robert Mueller as special counsel in charge of overseeing the investigation.

Mueller's team has cast a wide net in its probe, looking at multiple Trump confidants like former campaign manager Paul Manafort and former national security adviser Michael Flynn.

Mueller is also diving into the Trump family's finances and business dealings, including Kushner's.

RELATED: Jared Kushner and Donald Trump through the years



26 PHOTOS Jared Kushner with Donald Trump through the years See Gallery Jared Kushner with Donald Trump through the years NEW YORK CITY, NY - OCTOBER 14: (L-R) Donald Trump, Donald Trump Jr. and Jared Kushner attend Quest and Q Magazines Host Ivanka Trump Book Party at Trump Tower on October 14, 2009 in New York City. (Photo by Patrick McMullan/Patrick McMullan via Getty Images) NEW YORK, NY - MARCH 09: Jared Kushner, Ivanka Trump and Donald Trump attend the COMEDY CENTRAL Roast of Donald Trump at the Hammerstein Ballroom on March 9, 2011 in New York City. (Photo by Jeff Kravitz/FilmMagic) NEW YORK, NY - MARCH 28: (L-R) Donald Trump, Ivanka Trump, Jared Kushner, Bonnie Brooks and Ivana Trump attend LORD & TAYLOR Launches IVANKA TRUMP's Spring 2012 Collection at Lord & Taylor on March 28, 2012 in New York City. (Photo by Patrick McMullan/Patrick McMullan via Getty Images) NEW YORK, NY - MAY 9: Ivanka Trump, Donald Trump, Chiu-Ti Jansen, Jared Kushner attend YUE MAGAZINE Gala Launch Party Hosted by JARED KUSHNER & CHIU-TI JANSEN at the Atrium at Trump Towers on May 09, 2012 in New York City (Photo by- MIREYA ACIERTO/Patrick McMullan via Getty Images) NEW YORK, NY - NOVEMBER 8: Donald Trump and Jared Kushner attend the The New York Observer- Masters of Real Estate at The Metropolitan Club on November 8, 2012 in New York City. (Photo by Mireya Acierto/Patrick McMullan via Getty Images) NEW YORK, NY - MARCH 14: (L-R) Donald Trump, Mayor Michael Bloomberg and Jared Kushner attend The New York Observer 25th Anniversary at Four Seasons Restaurant on March 14, 2013 in New York City. (Photo by Paul Bruinooge/Patrick McMullan via Getty Images) NEW YORK, NY - APRIL 1: (L-R) Jared Kushner, Donald Trump, Lara Spencer and David Haffenreffer attend The New York Observer's New Look Hosted by Jared Kushner and Joseph Meyer at Casa Lever on April 1, 2014 in New York City. (Photo by Patrick McMullan/Patrick McMullan via Getty Images) NEW YORK, NY - JUNE 16: (L-R) Eric Trump, Lara Yunaska Trump, Donald Trump, Barron Trump, Melania Trump, Vanessa Haydon Trump, Kai Madison Trump, Donald Trump Jr., Donald John Trump III, Ivanka Trump, Jared Kushner, and Tiffany Trump pose for photos on stage after Donald Trump announced his candidacy for the U.S. presidency at Trump Tower on June 16, 2015 in New York City. Trump is the 12th Republican who has announced running for the White House. (Photo by Christopher Gregory/Getty Images) Republican Presidential candidate Donald Trump at a campaign rally at Concord High School with his daughter Ivanka Trump, and son in law Jared Kushner in Concord, NH on January 18, 2016. (Photo by Rick Friedman/rickfriedman.com/Corbis via Getty Images) NEW YORK, NY - JULY 16: (L to R) Newly selected vice presidential running mate Mike Pence, governor of Indiana, Republican presidential candidate Donald Trump, daughter Ivanka Trump, her husband Jared Kushner and Vanessa Trump stand on stage at the end of an event at the Hilton Midtown Hotel, July 16, 2016 in New York City. On Friday, Trump announced on Twitter that he chose Pence to be his running mate. (Photo by Drew Angerer/Getty Images) American real estate developer and presidential candidate Donald Trump (center) greets family members on stage during the Republican National Convention at Quicken Loans Arena, Cleveland, Ohio, July 21, 2016. Pictured are, from left, daughter Ivanka Trump and her husband, Jared Kushner, Trump, his wife, Melania, and son, Barron. (Photo by David Hume Kennerly/Getty Images) UNITED STATES - JULY 12: GOP nominee Donald Trump, points to the crowd after accepting the GOP nomination to be President at the 2016 Republican National Convention in Cleveland, Ohio on Thursday July 21, 2016. Behind Trump from left are daughter Ivanka Trump, her husband Jared Kushner, daughter in law Vanessa Trump, and son Donald Trump, Jr. (File Photo By Bill Clark/CQ Roll Call) MANCHESTER, NH - NOVEMBER 07: Republican presidential nominee Donald Trump (C) is joined on stage by his family (L-R) Lara Yunaska, Eric Trump, Vannessa Trump, Donald Trump Jr., vice presidential candidate Mike Pence, Ivanka Trump, Jared Kushner and Tiffany Trump during a campaign rally at the SNHU Arena November 7, 2016 in Manchester, New Hampshire. With less than 24 hours until Election Day in the United States, Trump and his opponent, Democratic presidential nominee Hillary Clinton, are campaigning in key battleground states that each must win to take the White House. (Photo by Chip Somodevilla/Getty Images) NEW YORK, NY - NOVEMBER 08: President-elect Donald Trump embraces son in law Jared Kushner (R), as his daughter Ivanka Trump, (L), stands nearby, after his acceptance speech at the New York Hilton Midtown in the early morning hours of November 9, 2016 in New York City. Donald Trump defeated Democratic presidential nominee Hillary Clinton to become the 45th president of the United States. (Photo by Mark Wilson/Getty Images) INDIANAPOLIS, IN - DECEMBER 1: President-elect Donald Trump and Jared Kushner take a tour of Carrier Corporation in Indianapolis, IN on Thursday, Dec. 01, 2016. (Photo by Jabin Botsford/The Washington Post via Getty Images) WASHINGTON, DC - JANUARY 20: President Donald Trump shakes hands with Senate Minority Leader Chuck Schumer, D-N.Y, as he is joined by the Congressional leadership and his family while he formally signs his cabinet nominations into law, in the President's Room of the Senate, at the Capitol in Washington, January 20, 2017. From left are Senate Majority Leader Mitch McConnell, R-Ky., Senate Minority Leader Chuck Schumer, D-N.Y, Sen. Roy Blunt, R-Mo., Vice President Mike Pence and his wife Karen Pence, Jared Kushner, Donald Trump Jr., and Ivanka Trump. (Photo by J. Scott Applewhite - Pool/Getty Images) US President Donald Trump (L) congratulates his son-in-law and senior advisor Jared Kushner after the swearing-in of senior staff in the East Room of the White House on January 22, 2017 in Washington, DC. / AFP / MANDEL NGAN (Photo credit should read MANDEL NGAN/AFP/Getty Images) WASHINGTON, DC - JANUARY 23: Director of the National Economic Council Gary Cohn (L) and Senior Advisor Jared Kushner (R) listen to U.S. President Donald Trump deliver opening remarks during a meeting with business leaders in the Roosevelt Room at the White House January 23, 2017 in Washington, DC. Business leaders included Elon Musk of SpaceX, Mark Sutton of International Paper, Andrew Liveris of Dow Chemical, Mario Longhi of US Steel, Marillyn Hewson of Lockheed Martin, Wendell Weeks of Corning, Alex Gorsky of Johnson & Johnson, Michael Dell of Dell Technologies and others. (Photo by Chip Somodevilla/Getty Images) TOPSHOT - Senior Advisor Jared Kushner (L) and Secretary of Homeland Security John Kelly (R) listen while US President Donald Trump puts his papers away at the beginning of a meeting on cyber security in the Roosevelt Room of the White House January 31, 2017 in Washington, DC. / AFP / Brendan Smialowski (Photo credit should read BRENDAN SMIALOWSKI/AFP/Getty Images) WASHINGTON, DC - JANUARY 31: The name place card for White House Senior Advisor Jared Kushner, who is also the son-in-law of President Donald Trump, sits on the table before a meeting about cyber security in the Roosevelt Room at the White House January 31, 2017 in Washington, DC. Citing the hack of computers at the Democratic National Committee by Russia, Trump said that the private and public sectors must do more to prevent and protect against cyber attacks. (Photo by Chip Somodevilla/Getty Images) WASHINGTON, DC - JANUARY 31: Jared Kushner, senior adviser to President Trump, listens to President Trump during a listening session with cyber security experts in the Roosevelt Room the White House in Washington, DC on Tuesday, Jan. 31, 2017. (Photo by Jabin Botsford/The Washington Post via Getty Images) WASHINGTON, DC - FEBRUARY 3: President Donald Trump talks with IBM CEO Ginny Rometty, left, and adviser Jared Kushner before speaking to business leaders during a strategy and policy forum in the State Dining Room of the White House in Washington, DC on Friday, Feb. 03, 2017. (Photo by Jabin Botsford/The Washington Post via Getty Images) US President Donald Trump arrives alongside Vice President Mike Pence (C) and White House Senior Advisor Jared Kushner (R) during a meeting with manufacturing CEOs in the State Dining Room at the White House in Washington, DC, February 23, 2017. / AFP / SAUL LOEB (Photo credit should read SAUL LOEB/AFP/Getty Images) WASHINGTON, DC - MARCH 15: U.S. President Donald Trump waves while walking to a waiting Marine One helicopter with son-in-law and senior advisor Jared Kushner while departing the White House on March 15, 2017 in Washington, DC. Trump is scheduled to travel to Michigan and Tennessee today. (Photo by Win McNamee/Getty Images) US President Donald Trump (3rdL), White House senior advisor Jared Kushner (4thL), US Secretary of State Rex Tillerson (2ndL) and Italy's Prime Minister Paolo Gentiloni (hidden) take part in a bilateral meeting in Villa Taverna, the US ambassador's residence, in Rome on May 24, 2017. 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Kushner met separately with the Russian ambassador to the US and a Russian businessman in December. Those interactions that were already under scrutiny as part of the FBI probe, but sources informed The Washington Post of the financial focus of the investigation.

During the meeting at Trump Tower with the Russian ambassador, Sergey Kislyak, Kushner reportedly floated the possibility of establishing a back channel line of communication between the Trump transition team and Russia.

The White House has said that Kushner's subsequent meeting with Sergey Gorkov, CEO of Russia's state-owned Vnesheconombank, was unrelated to business matters. But the FBI is looking into whether Gorkov suggested to Kushner that Russian banks could finance the business ventures of Trump's associates if US sanctions were lifted or relaxed.

Kushner met with the Senate Intelligence Committee in late July and told reporters afterward that he "did not collude" with Russia during the election and added that he had "nothing to hide."

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