PARIS, France (AFP) – The French parliament on Thursday adopted a law aimed at guaranteeing equal pay rights for women, who earn on average one fifth less than their male counterparts.

The text sets a five-year target for wiping out pay inequalities, calling for more negotiations between companies and unions, but does not plan any coercive measures.

A national review, to be carried out in three years’ time, will decide whether to introduce financial penalties for offending employers.

“This is a last warning before sanctions,” said the minister for gender equality, Catherine Vautrin.

The text, which was adopted upon a second reading in the National Assembly, also includes a measure that will allow employees to take on temporary work contracts on top of a part-time job.

The proposal is notably aimed at single mothers who wish to supplement their part-time income, but has been criticised by the left-wing opposition as undermining French labour laws.