US Vice-President Mike Pence has welcomed an effort by a group of senators to refuse to certify Joe Biden's presidential election win. The 11 Republican senators and senators-elect, led by Ted Cruz, want a 10-day delay to audit unsubstantiated allegations of election fraud. The move is certain to fail as most senators are expected to endorse Mr Biden in the 6 January vote. Mr Biden, a Democrat, is due to be inaugurated as president on 20 January. President Donald Trump has refused to concede the 3 November election, repeatedly alleging fraud without providing any evidence. On Saturday he addressed state legislators in five states where he has been trying to overturn the result. He also spoke to Georgia's Republican Secretary of State Brad Raffensperger and later tweeted that the Georgia official had been "unwilling, or unable" to offer details of instances of fraud, which Mr Trump has alleged took place without providing evidence. The Washington Post reported, citing an audio recording of the call, that Mr Trump had asked Mr Raffensperger to "find" enough votes to overturn the result in the state. Mr Trump cajoled and threatened the Georgia official with unspecified consequences if he did not help, telling him he was running a "big risk", the paper said.