Former German chancellor Gerhard Schroeder’s close friendship with President Vladimir Putin and lucrative business dealings with Russia have for years been reluctantly tolerated at home.

But as war clouds gather over Ukraine and allies question Germany’s resolve, Schroeder is increasingly seen as potential liability to new chancellor and fellow Social Democrat Olaf Scholz, fuelling calls for a clean break with the pro-Kremlin lobbyist.

“Schroeder is a burden to Germany’s foreign policy and to his old party,” Der Spiegel weekly wrote. “He has clear goals. Not for his country, but for himself.”

Schroeder’s recent warning to Ukraine to stop its “sabre rattling” was met with widespread disbelief in Germany, even among longtime friends within the centre-left SPD party.

The previous week’s announcement that the 77-year-old is set to serve on the board of Russian state energy giant Gazprom did little to calm tempers, as did the revelation that Schroeder held talks about Russia with an SPD interior ministry official last month.

The controversy comes at an awkward time for Scholz, who faces a major test this week when he travels to Moscow for his first in-person talks with Putin since taking office.

Scholz has been accused of being slow to step into the diplomatic fray in the Ukraine crisis, and of muddying Germany’s message of being united with allies against the Russian threat.

After much prodding from the United States and other allies, Scholz recently toughened his stance on possible sanctions should Russia invade Ukraine, including halting the Gazprom-owned Nord Stream 2 gas pipeline.

It was Schroeder, chancellor from 1998-2005, who signed off on the first Nord Stream pipeline between Russia and Germany in his final weeks in office, and he currently heads the Nord Stream company’s shareholders’ committee.

He is also chairman of the board of directors of Russian oil giant Rosneft.

In a TV interview, Scholz denied being influenced by Schroeder ahead of the Moscow trip.

“I haven’t asked him for advice, he hasn’t given me any either,” he said. “There’s only one chancellor, and that’s me.”

Putin and Schroeder appear to have built “a genuine friendship, based on trust” back when Schroeder was in power, political scientist Ursula Muench told AFP.

But “it’s problematic when a former chancellor uses his past political activities and contacts to make money,” she said.

Germany’s SPD has historically championed close ties with Russia, born out of the “Ostpolitik” policy of rapprochement and dialogue with the then Soviet Union, devised by former SPD chancellor Willy Brandt in the 1970s.

Successive chancellors continued the policy to varying degrees, including Scholz’s centre-right predecessor Angela Merkel who focussed on the economic benefits of dealing with Russia – a strategy known as “Wandel durch Handel” in German, or “change through trade”.

But even among German politicians sympathetic to Russia and its longstanding grievance over NATO’s expansion, patience with Schroeder – who famously celebrated his 70th birthday with Putin in Saint Petersburg – is running out.

SPD veteran Rudolf Dressler told Spiegel that Schroeder’s behaviour was “embarrassing”, and urged the party leadership to ask Schroeder to refrain from commenting on political matters in public.

Opposition politicians and those from the SPD’s junior coalition party, the liberal FDP, have called for Schroeder to lose his privileges as ex-chancellor – including an office with staff and a driver.

German taxpayers should no longer “finance Russian lobbying”, MP Volker Ullrich from the conservative CSU party told Bild newspaper, suggesting Gazprom pay for Schroeder’s upkeep.

Sudha David-Wilp, deputy director of the German Marshall Fund think tank in Berlin, said the latest Schroeder saga was “a distraction” in the Ukraine crisis, but nothing new.

“Everybody knows where Schroeder stands, everybody knows where he is getting his source of income from,” she told AFP.

More interesting is how Scholz and the SPD choose to navigate relations with Russia in the future, she said.

“Is there now an understanding that ‘Ostpolitik’ or ‘Wandel durch Handel’ is a thing of the past? Or will they keep using the same formula?” she asked.