German Chancellor and chairwoman of the German Christian Democratic Union, Angela Merkel. Photo / AP
Opponents of Chancellor Angela Merkel are turning to Momentum-style tactics in an attempt to stop her forming a new government in Germany.
A rebel movement is urging thousands of people to become members of the centre-left Social Democrat Party (SPD) in order to block it joining a new coalition under Merkel.
The initiative is being spearheaded by the SPD's youth wing, the Jusos, which narrowly failed to stop the party entering formal coalition negotiations in a vote at the weekend.
A final deal still has to be approved by a full vote of the membership, and the Jusos activists believe they can recruit enough members to block it.
"For the next step, we need you NOW," Kevin Kühnert, the Jusos' 28-year-old leader, tweeted alongside a link to apply for SPD membership.
"Now it's important to get as many coalition critics into the party as possible, so we can overturn the result in the membership vote," Frederick Cordes, a regional Jusos leader, said. "We're planning a national campaign under the slogan, 'a tenner against the coalition'."
The slogan refers to the cost of two months' party membership. The monthly fees are only €5 for those earning up to €12,000 a year - which includes many of the -Jusos' target demographic of students and young people.
The idea - reminiscent of Momentum's efforts to pack the British Labour Party with Jeremy Corbyn supporters - is also backed by a left-wing faction within the SPD, the Democratic Left Forum 21, who have come up with their own slogan: "Come in, say No!"
The SPD said there had been hundreds of new membership applications since the weekend vote in favour of coalition talks.
However, the Jusos and its allies have a major task before them.
The party currently has 440,000 members, and it says it will set a deadline for new members to join by if they want to vote.
Delegates at a special party congress narrowly voted in favour of formal coalition talks at the weekend, with just 56 per cent in favour.
Most commentators believe the current membership is more likely to support a coalition than the highly politicised delegates, though there is no reliable polling data.
Leading voices in the parliamentary party have spoken out against the plan.
"I have a problem with people -saying: join just so you can vote, and then you can resign," Matthias Miersch, a prominent left-leaning MP, said. "Party membership means values, and that's crucial."
Kühnert later distanced himself from the idea of two-month memberships, writing on Twitter: "We want to recruit new members who join the SPD out of conviction."
But the initiative has left Merkel with one more obstacle in the way of forming a new government.
It has also potentially given the SPD a stronger hand at negotiations which are expected to begin later this week. With the threat of an eventual No vote, the party's negotiators will hope to win more concessions from Merkel's Christian Democrats (CDU).
The narrow vote in favour of negotiations left the position of Martin Schulz, the SPD leader, severely weakened, with many questioning his future.
His performance at Monday's congress was generally considered to be lacklustre, with many commentators suggesting he was only saved from defeat by an altogether more rousing speech in favour of a coalition from Andrea Nahles, one of his rivals for the SPD leadership.
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