UKIP leader Paul Nuttall is to stand in Boston and Skegness in Lincolnshire in June's General Election.
Announcing his bid on Saturday, he said the seat voted "overwhelmingly" for Leave in the EU referendum last year.
The constituency, held by the Conservatives in 2015 with UKIP second, recorded the highest Leave vote, with 75.6% choosing to leave the EU.
Mr Nuttall said he would make it his "mission" to "ensure there is no backsliding on Brexit".
He had said on Friday that he would do his "duty to lead the party into battle" and stand for election, but at that time refused to confirm speculation he would stand in the Lincolnshire constituency.
Mr Nuttall had been due to make a speech in Hartlepool on Saturday as part of the election campaign, but a party spokesman said it had been cancelled due to "unforeseen circumstances".
Police said two women, aged 28 and 62, were arrested on suspicion of assault after an altercation broke out as supporters of the party waited for Mr Nuttall to arrive.
Poles don't vote UKIP he'll come last
