France's prime minister and the country's trade unions have failed in their latest bid to reach a breakthrough and end continuing strikes over pension reform.

The two sides met at the Labor Ministry in central Paris on Tuesday morning, but the only agreement they reached was to hold more talks on Friday.

Before the meeting, the prime minister appeared on French breakfast news shows doubling down on claims he and his fellow cabinet ministers have been intransigent when it comes to compromise.

Instead, Edouard Philippe said he was open to discussing changes to the average retirement age.

"I made a proposition in my speech in December at the Economic, Social and Environmental Council," said Philippe. "I said that balance was important and I proposed to guarantee it by putting in place a pivot retirement age, but if trade unions and employers' unions agree on a better system, I'll take it." He added: "That's a considerable degree of open-mindedness."

The leftist CGT union was not wooed by the prime minister, with leader Philippe Martinez reinforcing his position.

"That [offer from the prime minister] is a declaration of intent," said Martinez. "The government and the president have a dogmatic position which is 'People have to work longer,' we disagree. And 'There's no money,' we disagree with that, too."

The rolling strikes that have been ongoing for more than a month are continuing to hit transport across the country. Workers from oil refineries also took industrial action on Tuesday – one of four days of planned strikes. The unions have voted to continue the action, despite government plans to deploy police around oil depots to prevent fuel shortages.

The pension reforms causing such unrest stem from a manifesto pledge made by President Emmanuel Macron, who said he would not raise the retirement age but try to simplify the dozens of different pension regimes into one.

France spends about 14 percent of its GDP on pensions and the government believes its plans will make supporting those who have retired more financially sustainable.

There is another nationwide walkout planned for Thursday as anger and concern over the government's plans continue to simmer.