Warsaw  - Some 20,000 Polish postal workers went on strike Tuesday to press demands for higher pay amid a stalemate in talks with executives.

Protesters are demanding a 537-zloty (246-dollar) raise, while management has offered 305 zloty (140 dollars).

Bogumil Nowicki of the Solidarnosc trade union told Polish Radio that 66,000 postal workers voted for the strike.

But Zbigniew Baranowski, a spokesman for the Polish Post, said a raise seemed out of the question. A salary hike previously agreed for other postal workers will already cost the service 40 million zloty a month, the Rzeczpospolita daily said.

About 3 per cent of postal workers are taking part in the strike. Nationwide, most post offices are open for business, but distribution centers were closed in Warsaw and several other major cities.

Customers may begin to feel the effects of the strike on Tuesday evening, union organizers said. (dpa)