MONTREUIL, France — Emboldened French unions will hold two new rounds of nationwide protests next month against the government's plans to raise the retirement age, labor leaders said today, a day after strikes brought at least 1 million protesters onto the streets.

Representatives of six major unions meeting in the Paris suburb of Montreuil said another round of protests will be held Oct. 2 followed up by a strike and demonstrations Oct. 12.

Today's announcement of new protests coincided with a pledge by Prime Minister Francois Fillon to stand firm on the contested measures, despite the recent protests and polls suggesting a majority of French people support the strikers. The reform includes raising the retirement age from 60 to 62.

Thursday's strikes, the second round this month, hobbled trains, planes and schools throughout France. More than 200 demonstrations were held in cities and towns throughout the country, attracting a total of 1 million participants, according to police estimates, or 3 million, according to organizers.

Speaking to members of the governing UMP party in the Atlantic coastal city of Biarritz, Fillon insisted the reform is necessary to save the country's money-losing retirement system.