Sahra Wagenknecht, a firebrand MP from far-left Die Linke party and a stalwart of opposition politics since the fall of the Berlin Wall, said she was starting a new political association named after herself.
The Alliance Sahra Wagenknecht (BSW), which includes nine other deputies, would be leaving the Linke to focus on forming its own party by early next year and participating in European elections in June.
"The way things are going can't continue," Wagenknecht, 54, told a packed news conference.
"Otherwise we probably wouldn't recognise our country in 10 years," she said, denouncing "unchecked migration" which she blamed for exacerbating "the problems in our schools, above all in poor neighbourhoods".
Wagenknecht said her new political outfit would also mark a sharp departure "from the blind, haphazard eco-activism that makes people's lives even more expensive without doing anything to help the climate".
The Linke, which has its roots in both East German communism and the West German labour movement, has long been riven by strife and is teetering on the five-percent voter support hurdle to representation in parliament.
The defection of Wagenknecht's team could eventually sound its death knell.
But analysts focused primarily on BSW's potential threat to the far-right Alternative for Germany (AfD), which has surged in strength on migration fears and economic woes.
'Anger, desperation'
"The Wagenknecht party will skim off AfD votes -- what we're seeing is an alternative to the Alternative for Germany," political scientist Andrea Roemmele of Berlin's Hertie School of Governance told public broadcaster ZDF.
The AfD is polling at around 22 percent, far ahead of all three parties in Chancellor Olaf Scholz's unpopular centre-left-led ruling coalition.
A survey by the independent INSA opinion research institute showed that 27 percent of German voters would consider backing the new far-left party.
"There could be a gap in the market for her mix of anti-Americanism, Putin apologism, socialism, migration scepticism as well as openness to conspiracy theories," Der Spiegel journalist Mathieu von Rohr said.
Wagenknecht, as a fixture on political chat shows, has frequently blamed the West and NATO for Russia's invasion of Ukraine while stirring doubts about government measures to control the spread of the coronavirus during the pandemic.
With three east German state elections due next year where the AfD is expected to perform well, analysts said Wagenknecht's new party could fracture the vote, making it more difficult for mainstream democratic parties to form a government.
Wagenknecht, who grew up in communist East Germany as the child of an Iranian father and a German mother, said she had no intention of cooperating with the far right.
"We are preparing to launch a party so that all the people who have considered voting for the AfD or have already done so out of anger, out of desperation think twice and have a serious place to turn to," she said.
She said Germany was plagued by "pressure to conform" and cited unspecified polls indicating nearly half the population did not feel comfortable voicing their opinions for fear of criticism.
MP Christian Leye, who quit Die Linke to join BSW, told reporters the new party would seek votes among "people with low and mid-range incomes, pensioners, unionists and works council members" -- groups he said were underrepresented in German politics.
Asked about the BSW, Scholz's spokeswoman Christiane Hoffmann said the government saw no grounds for panic: "The chancellor is happy we live in a free country where parties can be founded."
