Germany's centre-left Social Democrats (SPD) set up an election showdown Sunday, picking Foreign Minister Frank-Walter Steinmeier to run against Chancellor Angela Merkel in elections in 2009.

After a meeting near Berlin of key SPD figures that also saw the unpopular chairman of two years Kurt Beck resign, Steinmeier said he would fight to ensure that his party would win next September's vote.

"The party needs a strong leadership and a strong centre and I believe that today's decisions set the course for this," Steinmeier told a news conference.

"We are better equipped than many people think and we ... will fight together and decisively so that in 365 days a Social Democrat is in charge again."

To help him do this, Steinmeier said party leaders wanted Franz Muentefering, a close ally of former SPD chancellor Gerhard Schroeder, to return as party chairman to replace Beck.

The choice of Steinmeier -- who is also Germany's vice-chancellor -- will see a battle between the two most senior figures in the ruling "grand coalition" of the SPD and Merkel's conservative Christian Democrats (CDU/CSU).

But the bespectacled, silver-haired 52-year-old -- who has never run for public office -- will have his work cut out to pose a real challenge to German's popular first female chancellor in 12 months' time.

Born in January 1956 in a small town in Lower Saxony in the old West Germany, Steinmeier had a reputation on the football field as being a team-player and an efficient all-rounder ready to play any position.

He served as chief of staff in Schroeder's centre-left ruling coalition with the Greens of 1998 to 2005, helping to shape behind the scenes an effective but unpopular package of economic reforms known as Agenda 2010.

After elections in 2005 left neither the CDU nor the SPD with enough seats to rule with their preferred coalition partners, Steinmeier emerged from the shadows when Schroeder put forward his protege as a possible foreign minister.

In the ensuing SPD-CDU "grand coalition" under Merkel, Steinmeier duly took on the job in November 2005, becoming in time a well-known and respected figure on the diplomatic scene.

But three years later many wonder whether he has the killer instincts needed for the rough-and-tumble of party politics, with even supporters worrying that taking on Merkel, 54, will be suicide.

Steinmeier will also need all the skills he can muster to fly the flag for a party that is split and which the latest opinion polls suggest is heading for disaster next time voters go the polls.

A survey of voters by the Forsa institute published on August 28 gave the SPD just 20 percent, only five points ahead of the far-left Die Linke, the new force in German politics.

Winning back voters from Die Linke, (The Left), a party formed just over a year ago by communists from the former East Germany and SPD defectors, looks set to be Steinmeier's biggest challenge.

Tapping into public anger about the erosion of the welfare state, Die Linke now holds seats in 10 of Germany's 16 regional parliaments.

Berlin has played a high profile in the wake of the Georgia conflict and is one of six powers holding talks with Iran over its nuclear programme, but Steinmeier's new status risks bringing out into the open damaging foreign policy differences with Merkel.

Already it is known that the two have not always seen eye to eye, most notably when Steinmeier barely managed to disguise his dismay at Merkel's decision to ignore Chinese anger and meet the Dalai Lama in September 2007.