LONDON, United Kingdom (AFP) – Jeremy Corbyn, the embattled chief of Britain’s main opposition Labour Party, will finally face a leadership challenge after Angela Eagle announced Saturday she would stand against the veteran socialist.

Eagle announced her bid following the collapse of peace talks aimed at resolving the deep crisis surrounding Corbyn’s leadership of the left-of-centre party.

“On Monday morning I will announce my candidature for leader of the Labour Party,” she said.

“I will explain my vision for the country and the difference a strong Labour Party can make.”

Corbyn, who has lost the support of at least three quarters of Labour lawmakers, had “failed to fulfil his first and foremost duty, that is to lead an organised and effective Parliamentary Labour Party”, said Eagle.

She said Labour under Corbyn could not hold the government to account or demonstrate it was ready to form a government itself in the event of a general election.

Eagle, 55, was the shadow first secretary of state — implying seniority over other front-bench spokespersons — before she and a host of others quit the so-called shadow cabinet over Corbyn’s leadership in the referendum on Britain’s membership of the European Union.

The party and the wider Labour movement backed Britain staying in the EU, but she and others blasted Corbyn for what they said was his lacklustre effort in persuading Labour voters.

Corbyn has vowed to battle on as leader, citing a groundswell of support in the party membership, despite only 17 percent of Labour members of parliament backing him in a vote of confidence, while 75 percent of his MPs voted against him.

Eagle, a former trade unionist — and a junior chess champion in her youth — would become the first openly gay leader of one of Britain’s main political parties if she wins the support of party members.

Eagle is a figure from the leftist spectrum of the party and never really associated with the more centre-left policies of Tony Blair and Gordon Brown.

In her letter announcing her resignation, Eagle wrote a scathing letter to Corbyn.

“Under your leadership the case to remain in the EU was made with half-hearted ambivalence rather than full-throated clarity,” she wrote.

“In such turbulent times, we need a leader who can unite rather than divide the Labour Party.”