Opposition leader Viktor Yanukovich and Prime Minister Yulia Tymoshenko are to compete in a run-off vote in the Ukrainian presidential election, exit polls showed on Sunday.

A woman gets her ballot at a polling station in Kiev, capital of Ukraine, on Jan. 17, 2010. Ukrainian voters started to cast votes on Sunday to choose their next president out of 18 candidates. [Song Zongli/Xinhua]

Yanukovich led in first round of voting with 36.6 percent of the vote, while his key opponent Tymoshenko scored 25.8 percent, an exit poll conducted by local television channel Inter showed.

Sergei Tigipko, a former economy minister, gained 13.5 percent and incumbent President Viktor Yushchenko got only 5.2 percent, according to Inter's exit poll.

Yanukovich also led in five other exit polls carried out by different agencies, all with more than 30 percent voting for him. Tymoshenko came only second to Yanukovich in all the exit polls. Therefore, the two will face each other in a second round of voting scheduled for Feb. 7.

Tymoshenko called on democratic candidates to unite so as to help her win the run-off.

"I am open for talks from now on, so that one can move on as a part of united democratic forces," she told a press briefing on Sunday evening.

Ukraine's Prime Minister Yulia Tymoshenko (C) casts her ballot during the presidential election at a polling station in Dnipropetrovsk January 17, 2010. [Xinhua]

Tymoshenko said she believes that 60 percent of the voters are in support of democratic forces.