Germany's ruling coalition stands under a test of unity as German Chancellor Olaf Scholz scrambles to amend the crisis that risks the fall of his government by holding an urgent meeting on Sunday between the trio, AFP reported.

Scholz's Social Democrats (SPD), the Greens, and the Free Democratic Party (FDP) formed an alliance a little over a year, which secured the Chancellor's appointment. But now, the relations among the alliance have been dwindling.

Vice Chancellor and Economy Minister Robert Habeck of the Greens party accused FDP of hindering the government's progress.

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The three-way alliance formed the government in December 2021 under "Dare for more progress" campaign motto.

Only two months later, the first critical test of the government began upon the start of the war in Ukraine, which deeply impacted the German economy and the political status quo with regard to vital relations with Russia.

The alliance between the Greens and the FDP is in no way natural, as the former's policies aim at more environmentally friendly decisions, including eliminating the use of nuclear energy and fossil fuels, while the latter is more business-oriented and focuses more on the economic aspect of any decision.

Read more: EU, Germany strike deal on fossil fuel car phaseout plan after dispute 

It does not work "that in a coalition of progress only one coalition partner is responsible for progress and the others for preventing progress," Habeck said earlier this week during a Green party event.

- Green vs. Cost -

Sunday's meeting between the allied parties would be a good opportunity to overcome obstacles on priority issues, Habeck said during an interview with ARD news outlet, while announcing his discontent over previous policy leaks.

Habeck's Green party revealed earlier a plan to ban the installation of new oil and gas boilers starting in 2024 rather than the previously announced date of 2025.

He also promised that the government will provide billions of euros to support the transformation from fossil fuels to greener alternatives such as heat pumps. But his plan was highly criticized over its immense cost and other safety issues.

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"The plans must go back to the drawing board and be fundamentally revised," Finance Minister and head of FDP Christian Lindner stated after a policy draft was leaked to the German newspaper Bild. 

Kubicki said Habeck and Putin had something in common, both sharing a "similar belief that the state, the leader, the chosen one, knows better than the people what is good for them."

The head of SPD, Saskia Esken Lars Klingbeil, called on the ruling partners to "find a new way of working".

"This is an appeal to all three parties in government -- these public arguments must stop now," he said.

- Don't fit together -

Other than the boiler's plan, the three-way coalition has disputed on several other issues, including child benefits, pension reform, and restructuring the rigged bureaucratic system - to speed up decisions over rehabilitating and modernizing Germany's rusty infrastructure.

EU's plan to ban cars using fossil fuels from 2035 has also raised some heated arguments between the two parties. While this plan aligns with the Green's political identity, the FDP opposed the union's roadmap and insisted on finding alternatives to engines functioning on fuel combustion.

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Further quarrels over budget spending and financial policies are threatening the existence of the alliance.

According to political scientist Juergen Falter, if Scholz fails to support his minister of finance, the coalition will be disbanded, as reported by Bild.

"The ideas of the Greens and the FDP simply do not fit together," he added, noting that it will always be difficult to place a middle ground to their opposing views.

"Three-way alliances automatically have more explosive material."