The former Breitbart chairperson also reportedly threatened to quit amid power struggle with Trump's son-in-law and senior adviser Jared Kushner. Trump’s campaign manager and chief strategist allegedly did not like Trump’s family influence.
Kushner reportedly told colleagues that Bannon’s nationalist agenda of deconstructing the government was hurting the commander-in-chief.
Bannon's removal from the NSC, which includes senior members of Trump's foreign policy team, was seen as a boost to national security adviser H.R. McMaster, who officials said has struggled to work together with Bannon.
A senior White House official, speaking on condition of anonymity, said Bannon's presence on the NSC was no longer needed after the departure of Trump's first national security adviser, Michael Flynn.
Flynn was forced to resign in February over his contacts with Russia's ambassador to the United States, Sergei Kisylak, prior to Trump's taking office on Jan. 20.
The official said Bannon had been placed on the NSC originally as a check on Flynn and had only ever attended one of the NSC's regular meetings.