US Congress handed Donald Trump a major defeat in the waning days of his presidency, as the Republican-led Senate voted to override his veto of a sweeping defence bill – the first time legislators have done so during his presidency. With more than 80 of the 100 senators voting to override, well more than the two-thirds required, the Senate approved the $740.5 billion National Defence Authorisation Act to fund the military for fiscal 2021. The Democratic-led House of Representatives had voted 322 to 87 on Monday to override Trump's veto. The votes to override Mr Trump’s veto reflects a widening rift between the president and some congressional Republicans, who stood by him through previous conflicts, as his influence ebbs. More GOP politicians, including Senate Majority Leader Mitch McConnell, in recent weeks have recognised Joe Biden as the winner of the presidential election. “Not once in six decades has a Congress let its differences prevent it from completing this work for our national security and our men and women who wear the uniform,” Mr McConnell said on Tuesday on the Senate floor in backing the veto override. “For the brave men and women of the United States armed forces, failure is simply not an option. So when it’s our turn in Congress to have their backs, failure is not an option either,” he said. Republican Jim Inhofe, chairman of the Sentae's Armed Services Committee, said the bill was "absolutely vital to our national security and our troops". "Our men and women who volunteer to wear the uniform shouldn't be denied what they need – ever." House Speaker Nancy Pelosi hailed the "resounding rebuke" that both houses of Congress delivered by overwhelmingly overriding Mr Trump's veto. "Instead of keeping Americans safe, the president continues to use his final moments in office to sow chaos and undermine our security," she said in a statement. Although many of Mr Trump’s voters remain loyal to the president, a number of Republican lawmakers share concerns over his recent behaviour. The split comes at a dangerous time politically for the GOP – just days before two runoff races in Georgia that will determine control of the Senate. Mr Trump vetoed the annual defence measure because he wanted to attach an unrelated provision to eliminate Section 230 of the Communications Decency Act, which protects technology companies from liability for most content published by their users. "Our Republican Senate just missed the opportunity to get rid of Section 230, which gives unlimited power to Big Tech companies," Mr Trump tweeted after the vote. "Pathetic!!!" He also took issue with the bill because it contains a provision for renaming military installations that honour Confederate generals. In his veto message, Mr Trump called the bill a “gift” to China and Russia without clearly articulating his reasoning.