 Adonis considered standing to be Labour's candidate for Mayor of London in 2016, but ended his putative campaign in February 2015, endorsing Tessa Jowell.In October 2015, he resigned the Labour Party whip in the House of Lords to sit as a non-affiliated Peer and lead a newly created National Infrastructure Commission (NIC).However, he resigned from the NIC in December 2017 because of the HM Government's approach to Brexit, saying the UK was "hurtling towards the EU's emergency exit with no credible plan for the future of British trade and European co-operation".