Poland's political stability has been upset by the dismissal of the Peasants' Party from the coalition government it had formed with the ex-communist Democratic Left Alliance following a row about new taxes.
If a new coalition partner is not found the minority government will remain vulnerable to defeat through the next three months of campaigning in the referendum on joining the European Union. Another election less than halfway through the government's term could produce major political change, possibly affecting EU accession.
These events were sparked by the decision of the Peasants' Party to vote against a government plan to bring in a new tax disk to be used as part-finance for EU road-building projects. It was the last straw for the prime minister, Mr Leszek Miller, following months of wrangling on related issues. As he put it, "you can't be in government and opposition at the same time".
A radical reform plan to ensure Poland can adapt to the financial discipline of EU membership was announced last week, which will require constant vigilance to implement. Ensuring his parliamentary majority will prove to be a continuing distraction from that task.
Unemployment, at 19 per cent, has become a huge problem for the Polish government, as have the low growth and high interest rates inherited from the previous centre-right administration. Structural reforms to address them have yet to take effect.
This transition, coinciding as it does with the closing stages of the EU accession negotiations and preparations for the referendum, has given much ammunition to opponents of the EU and has sharply reduced the government's popularity. Many voters have become disillusioned with politics. As a result, while support for joining the EU has remained relatively high, the turnout in the referendum may be less than the 50 per cent needed constitutionally to validate it.
As much the largest State about to join the EU, Poland has a particular importance for its historic enlargement. Its changing politics thereby become more salient for the existing member-states, just as its economic welfare increasingly affects market confidence. In the Czech Republic, another political crisis has also raised some doubts about support for EU accession.
The election last week of the long-standing Eurosceptic, Mr Vaclav Klaus, as president to succeed Mr Vaclav Havel has led the Czech prime minister, Mr Vladimir Spidla, to call a vote of confidence in his government. Since the Czech referendum is to be held only one week after the Polish one, these two sets of events could now have wider European ramifications.