Spidla's comments in Austrian news weekly Format raised the prospect that Joerg Haider's Freedom Party would object in earnest to the Czech Republic taking part in the European Union's planned eastward expansion.Austrian political parties had been hoping that Spidla, whose Social Democrats led in June elections and are expected to form a government, would reverse the previous government's loyalty to the Temelin power plant, some 60 km (37 miles) from Austria's border.
But in Friday's edition of Format, Spidla - who in 1998 as deputy prime minister voted against completing the plant - said he would instead stick by safety monitoring agreements reached with Austria and the EU last year.
"When you look ahead, it is clear that nuclear energy has a future. Temelin is a good nuclear power plant," Spidla said.
The Freedom Party's parliamentary leader Peter Westenthaler reacted sharply, renewing veto threats that had subsided last year with the agreement on independent safety monitoring at Temelin.
"If this is the line of the new Czech government, then it is the Czech Republic's ticket to being economically isolated," said Westenthaler. "The Czechs will never belong to the EU."
Temelin, a Soviet-designed plant with U.S. safety controls, has been a major source of tension between Prague and fervently anti-nuclear Austria.
Chancellor Wolfgang Schuessel, whose People's Party forms a centre-right coalition with the Freedom Party, has rejected past calls for blocking Czech EU membership over Temelin.
It was unclear how the Freedom Party could block Czech membership if the EU Commission and member governments agree as planned later this year which of 12 candidates can join the 15-nation bloc.
That agreement must be ratified by national parliaments of EU member states, which is where the Freedom Party could best bring its weight to bear. It has as many seats as the pro-expansion People's Party.
But the enlargement deal is likely to be presented as a package to be accepted or rejected as a whole, preventing individual parliaments from picking out single candidates, officials have said.