Russia could sharply raise gas prices for Ukraine if the ex-Soviet republic forms a pro-Western government following elections Sunday, the Kommersant newspaper reported, according to Sharecost.

"The gas price will be decided in negotiations. Everything will depend on the composition of the government," Russia`s ambassador to Kiev, Viktor Chernomyrdin, was quoted as saying.

Separately, a "highly placed" source told the newspaper that Ukraine would see a price hike whatever the result of Sunday`s parliamentary poll.

However, if Prime Minister Viktor Yanukovych, who has close ties to Moscow, keeps his post then the price will increase to 145-175 usd per 1,000 cubic metres, up from the current 130 usd.

If Yanukovych is ousted and "Orange Revolution" leader Yuliya Tymoshenko takes over as premier, then the price may rise to as much as 230 usd, the source was quoted as saying.

A close result is expected in the election, which would force President Viktor Yushchenko to hold coalition talks with either Yanukovych or Tymoshenko.

The three leaders have dominated Ukrainian politics since the 2004 "Orange Revolution" in which Yushchenko, helped by Tymoshenko, overturned Yanukovych`s declared victory in rigged presidential elections.

A gas price dispute between Ukraine and Russia in 2006 led to a brief cut-off of supplies, hitting deliveries further downstream in western Europe.