PARIS -- Managers of automaker Renault (IW 1000/78) threatened on Tuesday to close two sites in France unless trade unions agreed to measures aimed at raising the group's competitive performance, union officials said.

"The management warned us: 'If you don't sign, two sites could be closed'," an official of the FO union said. Officials of two other unions confirmed the warning.

Renault, which announced last week plans to cut 7,500 jobs in France through natural attrition and early retirement, has pledged not to close any factories if unions agree to changes that allow the company to compete more effectively worldwide.

On Tuesday, Renault officials said "if there is not a deal it is a minimum of two sites that will close," according to Dominique Chauvin of the CFE-CGC union.

Renault officials "also spoke of not making any promises on the transfer of products currently planned for France," Chauvin added.

A Renault statement denied that the automaker had set such conditions. "Renault has never indicated that 'two sites' could be closed in the event that ongoing negotiations on the performance of French sites is not concluded," the statement said.

Chauvin identified the Flins plant outside Paris and another in Douai, northern France, as likely targets should plant closures be announced.

An aide to Industry Minister Arnaud Montebourg said Renault should continue negotiating in good faith with workers and that the talks "shouldn't resemble blackmail."

Montebourg last year threatened to nationalize an entire factory owned by steel giant ArcelorMittal when the company wanted to shut down two blast furnaces located there.

Among the measures that Renault is pushing for are a wage freeze this year and a harmonization of working hours along with additional job cuts through 2016.

The company last week reported a 6.3% fall in its 2012 sales to 2.55 million vehicles due to an 18% collapse of deliveries in Europe, but said it hopes for a rebound this year.

Copyright Agence France-Presse, 2013