German Chancellor Angela Merkel's conservatives will start talks with their defeated centre-left election rivals Friday, the first step on a long and thorny road that could end in a 'grand coalition' government.
Merkel, despite her September 22 election triumph, needs to team up with either the Social Democrats (SPD) or Greens party to ensure a majority after her previous allies, the Free Democrats, failed to win any seats.
Whatever the eventual outcome, the poker-game like talks are expected to drag on for weeks, as they have in the past, as negotiating partners will seek to extract the highest possible price on policies and ministerial posts.
The talks could even run into next year, warned SPD general secretary Andrea Nahles, who said "we could end up with the formation of a government in January or February".
The SPD is torn on whether to again govern in the shadow of the popular Merkel, as it did from 2005-09, when it failed to earn much credit for their joint achievements and ended up suffering two bruising election defeats in a row.
While another stab at power and winning ministerial posts is tempting for party leaders, many rank-and-file members of the 150-year-old party would prefer to attack the Merkel government from the opposition benches and regroup.
Merkel's Christian Democrats (CDU) for their part have sought to draw a line in the sand, vowing to oppose the SPD's campaign-trail demand to raise taxes on the rich to finance public spending.
"With us there will be no tax rises," CDU parliamentary leader Volker Kauder told ARD public television, stressing this was also Merkel's position.
A day earlier, Bavaria's powerful state premier and Merkel ally Horst Seehofer had vowed that "the citizens have my word" that the taxman would not place any additional demands on them.
SPD chief Sigmar Gabriel has meanwhile projected confidence, warning that, should the talks fail, his party is "not scared" of ending up in opposition or even facing fresh elections.
His party has also pledged to let its 470,000 members vote on whether to enter another uneasy marriage with the CDU or not.
In the exploratory talks on Friday at 1100 GMT, at least 14 conservatives -- including Merkel, Seehofer and Finance Minister Wolfgang Schaeuble -- will face off with seven delegates from the SPD.
The SPD's Nahles on Monday refused to be drawn on whether the party had any red-line demands, merely pointing to the SPD election manifesto, but vowed that it would not come out of the talks "empty-handed".
She dismissed as "private opinions" media reports on the SPD's negotiating positions, including a demand for six ministerial posts reported in the Frankfurter Allgemeine Sonntagszeitung newspaper.
Such demands are like "haggling in a bazaar" and ignore the election outcome which gave the CDU almost 42 percent and the SPD just over 25 percent, said political scientist Werner Weidenfeld of Munich's Ludwig Maximilian University.
"It damages trust in the political process," he told AFP. "It's tactical game-playing."
The CDU, to keep all options open, is also planning exploratory talks next week with the Greens, said CDU general secretary Hermann Groehe.
Such an alliance would have long seemed impossibly remote, bringing together the main conservative party with a group that emerged out of the 1970s anti-nuclear, peace and environmental movements.
However, Merkel after Japan's 2011 Fukushima disaster adopted the Greens' flagship demand of phasing out nuclear power, while the Greens have increasingly become a party of urban middle-class voters.
"We want serious and earnest exploratory talks, mindful that the policy differences are large," said the Greens' outgoing chairwoman Claudia Roth.
Amid the political manoeuvring, President Joachim Gauck was due to meet leaders of all major parties at his Bellevue Palace in Berlin, starting with a talk with Merkel on Monday.
Munich daily Sueddeutsche Zeitung reported that Gauck wanted to ask each of them how they assessed the tricky political situation and how to prevent political paralysis in Europe's biggest economy.