Brexit hardliner Boris Johnson has finally won the race to lead Britain's governing Conservative Party. Having defeated his rival Jeremy Hunt in a vote of Conservative Party members, he will become UK's next prime minister. He will be installed as PM in a formal handover from Theresa May which will take place on Wednesday. The victory is a triumph for the 55-year-old Johnson, an ambitious but erratic politician whose political career has veered between periods in high office and spells on the sidelines. Watch our video to know about the challenges that he would have to combat.