Europe's top human rights watchdog urged Ukrainian authorities Monday to conduct a free and fair parliamentary election next month, but warned that the imprisonment of Ukraine's top opposition leader bodes ill for the country.

The Oct. 28 election has already been tainted by the jailing of former Prime Minister Yulia Tymoshenko on abuse-of-office charges that the West condemns as politically motivated. Tymoshenko, who was sentenced to seven on charges of overstepping her authority when negotiating a 2009 gas deal with Russia, has accused President Viktor Yanukovych of throwing her in jail to bar her from the vote.

Council of Europe Secretary-General Thorbjorn Jagland condemned her imprisonment, but said the election must still take place and be honest.

"We recognize that there is a problem with one of the main leaders of the opposition ... in prison," Jagland told reporters in Kiev. "It would have been better to contest the decision of this gas deal at the political level, in the Parliament, by the people (themselves)."

"But still it is very important that the elections are being held and that they be free and fair," he said.

Tymoshenko, 51, the charismatic leader of the 2004 street protests dubbed the Orange Revolution that brought a pro-Western government to power, denies the accusations against her. Her jailing has harmed Ukraine's relations with the West and put on hold a key cooperation agreement with the European Union, which Kiev aspires to eventually join.

Yanukovych's fraud-tainted victory was annulled during the revolution, but he returned to power in 2010 by narrowly defeating Tymoshenko in the presidential vote, capitalizing on the slow pace of reforms and infighting in the Orange camp.

Yanukovych will struggle to retain his majority in Parliament after the opposition joined forces around Tymoshenko's imprisonment.

The opposition and rights groups accuse Yanukovych of concentrating too much power in his own hands over the past two years and undoing many of the democratic achievements of the Orange Revolution.

Yanukovych brushed aside that criticism Monday, telling Jagland in a meeting that Ukraine was consistently implementing democratic reforms.

"The past and the current year have been busy with implementing reforms aimed at strengthening democratic institutions," Yanukovych said in a statement posted on his website.