'We will debate, and you will vote,' Sebastien Lecornu promised / AFP

France's Prime Minister Sebastien Lecornu on Tuesday backed the suspension of an unpopular 2023 pensions reform, in a key move to bolster his cabinet's survival and draw his country out of political crisis.

France, the eurozone's second-largest economy, has been battling a deep political crisis since President Emmanuel Macron last year called snap elections to consolidate his power but instead lost his majority.

After parliament toppled his two predecessors over cost-cutting measures, Lecornu, the president's seventh premier since 2017, is battling to keep his cabinet alive long enough to pass a much-needed austerity budget by the end of the year.

The Socialists, a swing group in parliament, had threatened to vote to topple the government if he did not immediately suspend the pensions reform that raised the retirement age from 62 to 64.

"I will propose to parliament this autumn that we suspend the 2023 pension reform until the presidential election," Lecornu said.

"There will be no increase in the retirement age from now until January 2028."

The pension bill, which a previous government used a constitutional power to force through parliament without a vote in 2023, sparked months of angry protests.

Lecornu also promised parliament that he would not use the controversial tool to bypass a vote in the lower chamber on any draft laws, and put all proposed bills to debate.

"The government will make suggestions, we will debate, and you will vote," the 39-year-old Macron loyalist and former defence minister repeated throughout his speech.

But Lecornu warned suspending the pension reform would cost some 400 million euros ($463 million) in 2026 and 1.8 billion euros the year after, and it should be offset by savings.

- Under pressure -

The premier's speech follows a dramatic fortnight in French politics.

Lecornu, who became prime minister last month, resigned on Monday last week after criticism of his newly appointed government.

He was re-appointed on Friday and proposed a new team of ministers on Sunday -- just in time for government to approve and file a draft budget with parliament.

Lecornu is under severe pressure from opponents.

The hard-left France Unbowed party and far-right National Rally have already filed motions to topple Lecornu's new cabinet, although they stood little chance of succeeding without the backing of the Socialists.

It was not immediately clear how the Socialists would respond to Lecornu's promise on the pension bill.

Earlier on Tuesday, Macron had warned that any vote to topple Lecornu's cabinet would force him to dissolve parliament and call fresh elections.

Macron has also faced unprecedented criticism.

Some opposition leaders are urging him to call snap elections or resign, and even key allies such as former prime minister Edouard Philippe have distanced themselves from the 47-year-old president.

The far right senses its strongest chance yet to seize power in the 2027 presidential elections, when Macron's second and last term runs out.

France's debt-to-GDP ratio is the European Union's third-highest after Greece and Italy, and is close to twice the 60-percent limit fixed by EU rules.

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