PARIS (Reuters) -France's labour unions will keep up their fight against a planned rise of the legal retirement age, they said on Wednesday, after a meeting with Prime Minister Elisabeth Borne failed to end months of gridlock over a deeply unpopular reform.

"We will not come back to the negotiating table as if nothing had happened", said Cyril Chabanier, president of the CFTC union, reading out a joint statement after the meeting.

Wednesday's talks were the first high-stakes meeting between the government of President Emmanuel Macron and union bosses since nationwide protests and strikes against the reform bill started in January.

The next day of strikes and street is planned for Thursday.

Labour representatives complain they are not being listened to despite weeks of protest marches and unrest against the pension overhaul, which raises the legal retirement age to 64 from 62.

Chabanier said the unions told Borne the only way out of the deadlock was for the government to withdraw the reform, an option which he said she rejected.

The government says the changes are needed to balance the pension budget in years to come. The unions say the money can be found elsewhere.

Macron's drive to ram through the legislation without a final vote in parliament only added to the fury of unions and the wider public.

(Reporting by Tassilo Hummel, writing by Silvia Aloisi, editing by Richard Lough)