Macron election: French ex-PM Manuel Valls wants to join En Marche
French Socialist former Prime Minister Manuel Valls has said he wants to sign up to President-elect Emmanuel Macron's party to fight next month's parliamentary elections.
Mr Valls said the Socialists were dead and "I will be a candidate for the presidential majority".
Party officials reacted warily, saying he had 24 hours to sign up.
Emmanuel Macron won the presidency on Sunday and his new party has begun picking candidates for the June vote.
The party, which has changed its name from En Marche (On the move) to La République en Marche, intends to have a list of candidates ready for the June vote by Thursday, drawn up from across French politics and civil society. It was only created 13 months ago and has no representatives in the National Assembly.
Mr Valls resigned as prime minister when he stood unsuccessfully in the race to be Socialist presidential candidate and later backed Mr Macron to be president.
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However, his approach on Tuesday was not immediately welcomed with open arms.
Macron spokesman Benjamin Griveaux, told French radio that Mr Valls had not yet been registered as a candidate by the party.
"He should have applied like everyone else because the rules are the same for everyone. If you don't put your name forward you can't be selected by En Marche. He's got 24 hours," he said.
Mr Macron won 66.1% of the vote on Sunday, while far-right opponent Marine Le Pen attracted 33.9% of the vote. A quarter of the population abstained in the election and more than 11% either cast blank votes or spoilt their ballot.
'Treachery' at the heart of the Socialists
Mr Valls's assertion that the Socialists were dead prompted anger from party colleagues.
"I hope for France's sake that Brutus and Judas don't seek En Marche's party nomination," said Socialist MP Alexis Bachelay.
And the former prime minister's interview came hours after an eye-opening fly-on-the-wall TV documentary on Mr Macron's campaign. The programme showed the next president back in December describing Mr Valls's actions towards President François Hollande as "a real betrayal", shortly after Mr Hollande announced he would not run for a second term in office.
Mr Macron says in Behind the Scenes of a Victory that while he himself had left the government to avoid being party to the cynicism at the heart of the government, Mr Valls had remained and brought the president down from within. "If there is traitor, someone who has pulled the trigger on Hollande, it's Valls," he says.
The man who beat Mr Valls to the Socialist candidacy, Benoît Hamon, was all but wiped out in the first round of the presidential election, winning just 6.36% of the vote. Seen as a notorious party rebel, he had attracted little support from the Socialist leadership.
The timing of Mr Valls's comments was incendiary, shortly before the Socialists held a national meeting in an attempt to regroup after their electoral failure.
Macron: The days ahead
9 May: Mr Macron will mark the EU's Europe Day, the annual celebration of peace and unity in Europe. In his victory speeches on Sunday he focused on the need for a strong Europe
10 May: Marks France's Slavery Remembrance Day, then in the afternoon attends the funeral of Corinne Erhel, the legislator who collapsed and died while speaking at a Macron rally last Friday. Official election results are published
14 May: President François Hollande formally hands over power to Mr Macron
15 May He will name his choice of prime minister
15-19 May: Mr Macron must finalise candidates for his party in the parliamentary election
11 and 18 June: Parliamentary election held over two rounds. All 577 seats are being contested.