Sir Vince Cable is to run for the Liberal Democrats leadership, after previous leader Tim Farron stepped down.
The MP said in a statement: "With 20 years on the national political stage I am passionate as ever about our liberal values.
"I am ready to commit my energy, enthusiasm and experience to the task of leading the Liberal Democrats through what will be a period of chronic uncertainty.
"With the prospect of another election looming large, we must be ready for the fight."
He is the first member of the party to announce that he will run in the leadership election, according to Sky News.
The former business secretary has said he wants to conduct a second referendum on the Brexit deal, and if a deal is not good enough he wants the UK to have the option of staying in the EU.
He also claimed that there is a space in British politics for the Lib Dems to take as the Conservatives are in disarray and Labour's policies lack economic credibility.
Cable previously served as the acting leader of the party, when Sir Menzies Campbell resigned in 2007. However he decided not to run for leadership at that time because he thought he wouldn't be elected because of people's "irrational prejudice about age".
The new leader will be elected by party members through a postal vote before the annual party conference on September 16 in Bournemouth.