With six different party blocs in Germany's parliament after Sunday's election, conservative Chancellor Angela Merkel faces a jigsaw puzzle of unprecedented complexity to build a coalition.

As her current partners, the Social Democrats (SPD), plan to head into opposition after bruising losses, Merkel's best prospect for a parliamentary majority is an alliance of her conservatives, the pro-business Free Democrats (FDP) and the Greens - the first three-way government since the 1950s.

All parties aim to have a new government established by January, but many regard that timetable as optimistic and expect. In 2013, a relatively simple two-party agreement with the SPD took almost 100 days.

Until the Bundestag, the lower house of parliament, confirms a new coalition, Merkel's existing government remains in place. Following is a summary of what happens next: Parties are likely to be reluctant to make the compromises necessary for a coalition before Lower Saxony's snap regional election on Oct. 15, for fear of alienating supporters in a key state.

THE NEW PARLIAMENT CONVENES

The new Bundestag has until Oct. 24 to convene, by which time a new president or speaker must be chosen. The six blocs must also elect their parliamentary group leaders and other officials by then.

The current president of the Bundestag, Norbert Lammert of Merkel's Christian Democratic Union (CDU), is not up for re-election.

One option that has been floated is for Wolfgang Schaeuble, 75 and finance minister since 2009, to become Bundestag president to make way for one of the likely junior coalition partners to take the finance portfolio.

EXPLORATORY TALKS

Traditionally, the winner of the election invites potential coalition partners to exploratory talks to establish if they have sufficient common ground to work together.

Keen to maximize her room for maneuver, Merkel has said she wants to invite the SPD as well as the Greens and the FPD, even though the SPD's top leaders have already said they want to go into opposition.

All parties have ruled out working with the far-right Alternative for Germany (AfD) party, while the conservatives rule out working with the radical Left party, which has its origins in the East German Communist Party.

If talks with the FPD and Greens fail, pressure could grow on the SPD to revisit its decision. However, this would make the AfD the largest opposition party, with a privileged role in parliamentary committees - something the rest of the political establishment will want to avoid. The Lower Saxony election may mean the exploratory talks will be slower to start than usual.

Once exploratory talks have been completed, the parties that have agreed in principle to work together hold formal talks to thrash out a government programme that they are committed to implementing.

This process, which involves painstaking policy negotiation, can take over a month, even when only two parties are involved. If party members demand a vote on the programme, further delays can occur.

After the 2013 election, it took more than four weeks for formal coalition talks to begin, and they lasted another month. Merkel's new government was confirmed on Dec. 17 after SPD members approved the coalition deal, almost three months after the Sept. 22 election.

SCHAUEBLE PUSHED TO HEAD PARLIAMENT

Senior conservatives raised pressure on Wolfgang Schaeuble, 75, yesterday to give up the finance ministry and instead impose his authority as head of Germany's next parliament, which will include a large bloc of far-right members.

Schaeuble has held the ministry since 2009 but Sunday's election, in which Chancellor Angela Merkel's conservatives bled support to the far right and found themselves needing to build an untried coalition, has raised doubts over whether he can keep the job. The post is coveted in particular by the pro-business, low-tax FDP, whose support Merkel is likely to need, together with the Greens, to assemble a working majority. The tone in the new assembly is also likely to be made more abrasive by the Alternative for Germany (AfD), which stunned the establishment on Sunday by becoming the first far-right party to enter parliament in more than half a century.

Schaeuble has refused to discuss his future after the election, beyond signaling his desire to stay in politics. The current president, CDU lawmaker Norbert Lammert, is not up for re-election. The Bundestag president cannot simultaneously hold a ministerial post. Meanwhile, Frauke Petry, the co-leader of the far-right Alternative for Gemany (AfD), and her husband Marcus Pretzelli announced yesterday their intention to resign from the party. Petry, the highest-profile figure in the AfD's more moderate wing, had on Monday shocked other senior party figures by saying she would not sit with the AfD in the Bundestag lower house and would instead be an independent member of parliament.