Boris Johnson could be stopped from becoming prime minister even if he is elected as the new Conservative leader, The Guardian reported referring to two of Britain’s leading constitutional experts.

Some members of parliament are threatening to deprive the party of support if Johnson heads it, and Johnson is warned that he may be prevented from heading the government if it becomes clear that he cannot control the majority in the House of Representatives.

It risks involving the Queen in politics and could pull Theresa May back into the Brexit impasse; as the incumbent prime minister, she will be key in recommending to the palace who should be called to form the next government.

“Johnson’s legitimacy would be challenged if just a handful of Tory MPs declare that they could not support his administration, according to professors Robert Hazell and Meg Russell from the constitution unit at UCL, University of London. With May already struggling with a tiny working majority, two Tories – Dominic Grieve and Ken Clarke – have already indicated that they would not be able to support an administration that would leave the EU with no deal, which Johnson is willing to do,” the source added.