Polls are open in Ukraine in a parliamentary election that pits President Viktor Yanukovych's ruling party against the country's divided opposition.

Mr. Yanukovych's Party of Regions is expected to retain its majority.

Groups within and outside Ukraine are questioning the fairness of the vote.

More than 20 political parties are competing for 450 parliamentary seats, with half being filled by a majority system for the first time and the others through party lists.

Boxing heavyweight champion Vitaly Klitschko's UDAR party is in a tight opposition race with the coalition of former prime minister Yulia Tymoshenko for second place. The opposition leader is serving a seven-year sentence after being convicted of abuse of office last year.

Opponents of Mr. Yanukovych accuse him of keeping his chief rival imprisoned to prevent a repeat of the 2004 election in which he narrowly lost to the opposition.

The European Union has postponed agreements with Ukraine over Ms. Tymoshenko's conviction. An agreement with the International Monetary Fund signed shortly after Mr. Yanukovych came to power was also suspended after the government refused to raise utility prices sought by the IMF.

Earlier this month, a poll by the Democratic Initiatives Foundation of about 2,000 people found that only 9 percent of Ukrainian voters believe the parliamentary elections will be fair. In the same poll, some 47 percent of respondents said they believed the polls might be, or definitely will be “rigged.”

Some 36 million Ukrainians are eligible to vote in the election, which is being monitored by thousands of international and local observers.