The former army officer is facing widespread calls to quit after a scandal over racist text messages sent by his former girlfriend. Several his frontbench team stepped down on Monday, a day after the other members of Ukip’s national executive committee unanimously passed a vote of no confidence in him.
However, Mr Bolton has vowed to stay on and take the fight to his critics in the party.
He also secured the backing of former Ukip leader Nigel Farage, who said the party had to change or face being wiped out.
Speaking to reporters outside a hotel in Folkestone, the Ukip leader said it was up to party members to remove him. Following the NEC’s vote of no confidence, an emergency general meeting will be held within 28 days so members can decide whether Mr Bolton should continue in the role.
“I respect the next steps in the constitutional process and will therefore not be resigning as party leader,” he said. “I repeat: I shall not be resigning as party leader.”
“Instead, during the next four weeks I shall be calling for the coordination and mobilisation of all Leave campaigns, to ensure that the Government delivers full independence from the European Union in all areas of government and administration and I shall be calling for the party itself to mobilise to support this agenda.”
He added: “This is the most pressing matter facing our country and I am determined not to allow the NEC to distract the party away from participating forcefully in the independence debate.”
Attacking his critics in the party, Mr Bolton said: “Without reflecting at all on its individual members, the NEC, as presently constituted, is unfit for purpose and has severely handicapped the party’s progress and political delivery for some years, as all recent Ukip leaders will attest.
“It has not only lost the confidence of me as the party leader in its ability to act objectively as the party’s governing body; it has also lost the confidence of a large proportion of the membership.”
Mr Bolton said his party’s NEC required “significant and urgent reform” and that he would be proposing a new constitution, including reforms to the executive committee.
Echoing US President Donald Trump, he said: “In a single phrase, it is time to ‘drain the swamp’.”
Mr Bolton’s vow to cling on comes despite a number of senior Ukip figures calling on him to quit following revelations that his then-girlfriend, 25-year-old glamour model Jo Marney, had sent a series of racist text messages about the actress Meghan Markle, who is due to marry Prince Harry in May. The Ukip leader said he had ended the “romantic element” of his relationship with Ms Marney after the texts were made public.
As the scandal rumbled on, his deputy leader, Margot Parker, and assistant deputy, Mike Hookem, were among those who stepped down and criticised his leadership.
Ms Parker said: “It would be quicker and cleaner if he came to the conclusion he could go sooner rather than later.
“This is taking time away from doing the job. This puts the party in a limbo situation.”
But Mr Farage threw the beleaguered leader a lifeline, saying he "despaired" at the party's decision-making processes and praised Mr Bolton's decision to let an emergency meeting (EGM) of party members decide his fate.
Writing in The Telegraph, Mr Farage said: "Bolton knows as well as anyone that Ukip must reform or die. His refusal to accept the NEC decision to quit, and his insistence on carrying out a full EGM, could provide a lifeline for Ukip. For this crisis is about more than Henry Bolton. It is about whether Ukip is fit for purpose.
"As one party spokesman after another resigns, I am reminded of the nightmare Jeremy Corbyn faced in 2016 when 21 members of his shadow cabinet resigned.
"Corbyn was written off by the press, but the rank and file membership saved him. If Bolton has the courage and the vision to introduce a new constitution, and shows that he can be a strong spokesman for Britain leaving the single market, taking back its fisheries and restoring pride in the UK, he may well surprise all of his critics too."
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