Poland's ruling center-right coalition parties set themselves a two-week deadline on Tuesday to resolve a government crisis that threatens to harm the country's effort to join the European Union.

The liberal Freedom Union (UW), which on Sunday pulled out of a 30-month-old alliance with the larger, trade-union-based Solidarity bloc (AWS), said it was ready for talks on forming a new cabinet capable of implementing tough economic reforms. The UW's five ministers, who handed their resignations to Prime Minister Jerzy Buzek on Monday, attended the cabinet's weekly meeting. Their resignations were not accepted. Poland's financial markets have so far reacted calmly to the crisis and the Warsaw stock exchange rose 3.4 percent on Tuesday, but politicians said quick decisions were needed to stop the economy being affected. The UW is demanding that Buzek be replaced with a leader able to force often-unruly AWS deputies to support government legislation in parliament. Serious talks are expected to begin after Thursday, when the AWS national council is due to discuss the party's response to UW demands and approve a new candidate for premier.