BERLIN (AP) — Thousands of factory workers in Germany are staging short-term warning strikes to increase pressure on employers as talks got underway on a new labor agreement.

The IG Metall union said Thursday it had called for walkouts across the country as it seeks a 6 percent pay increase for some 3.9 million workers. It also wants employees to be able to reduce work weeks from 35 to 28 hours for up to two years with a guarantee they can return to regular hours.

Employers are offering a 2 percent rise and want the right to negotiate with employees to work more hours if they agree.

The union has being holding short labor stoppages this week and head Joerg Hofmann says they could escalate strikes if there's no progress by months' end.