Ralf Stegner, deputy party chairman of the Social Democrat Party (SPD), said he could see “no future” for the four-time Chancellor, after talks to form a new coalition government following a damaging election ended in failure.
Her prospective “Jamaica” alliance collapsed on Sunday evening as the liberal FDP walked away from talks, with party leader Christian Lindner claiming: “It is better not to govern than to govern badly.”
Now Mrs Merkel herself has conceded she would rather hold fresh elections than try to rule as a minority government.
In saying so, the German chancellor could well be signing her own death warrant.
Ultimately, the decision will now fall to Germany’s president Frank-Walter Steinmeier, who has the power to dissolve parliament and call an election or encourage Mrs Merkel to carry on her negotiations.
But any new election is likely to spark a challenge to Mrs Merkel’s leadership of the Christian Democratic Union (CDU), after the party suffered heavy losses in September’s ballot.
Mr Stegner’s SPD party, Ms Merkel’s former coalition partners, has already ruled out any deal this time around, vowing to go into opposition to fight the rise of the far-right Alternative for Germany in the Bundestag.
Speaking to German newspaper Express on Monday, Mr Stegner, who worked in education and research during the SDP/CDU coalition, said: “She has definitely failed.”
He ruled out any prospect of his party reversing its stance over opposition, saying: “The starting position for the SPD has not changed.
“We have no mandate for another grand coalition.”
But he blamed the leaders of all four parties involved for the failed “Jamaica” alliance – the CDU, FDP, Greens and Mrs Merkel’s Bavarian allies the Christian Social Union.
He said: ”Merkel, Özdemir, Seehofer and Lindner did not manage it, despite the fact they have told us for weeks what they want to do better.”
A senior figure in Germany’s Greens said the country could be heading for a new general election “around Easter”, with millions forced to go back to the polls.