The Gdansk shipyard now employs 3,000 people

Brussels has given Poland until the end of Tuesday to either close two of Gdansk's three slipways or else repay 51m euros ($69m; £35m) of European aid.

EU Competition Commissioner Neelie Kroes is now studying Poland's calls to keep open two slipways at Gdansk.

The shipyard is the birth place of the celebrated Solidarity trade union.

Solidarity founder Lech Walesa said he would consider it a "personal failure" if the Gdansk shipyard was not saved.

Anti-communist vanguard

Back in 1980, a strike by 17,000 ship builders at Gdansk saw Solidarity recognised as the first non-communist trade union in the then Soviet Eastern Bloc.

The move was one of the first successful steps that led to the eventual collapse of communism, not just in Poland but Eastern Europe as a whole.

Under communism Gdansk could count on regular work from the Soviet Union, but it has struggled to compete in the post-communist free market and now employs 3,000 people.

Solidarity's struggle helped inspire numerous anti-Soviet movements

The historical importance of the Gdansk shipyard is a central reason why the Polish government is loath to see its capacity cut too deeply.

The government argues that leaving Gdansk with just one slipway would turn it into "a tiny company instead of a shipyard".

However, under EU rules, state aid for struggling shipyards can only be granted if it is accompanied by extensive cost-cutting aimed at restoring long-term viability.

Another condition is that private investors must be brought on board.

Without such moves, the EU insists that the aid paid to Gdansk is illegal and therefore needs to be repaid.