Russian gas monopoly Gazprom has said it will cut Ukraine's gas supply by a further 25 per cent over a debt dispute.
Gazprom has already cut supplies by 25 per cent and has decided "to cut deliveries by another 25 per cent" at 1700 GMT on Tuesday, Sergei Kupriyanov, its spokesman said on state television.
The Gazprom spokesman also said that talks with Ukraine over the gas cut have not restarted.
Kupriyanov said gas supplies to Europe through Ukraine were uninterrupted, running at capacity at 356.6 million cubic metres of gas per day.
Ukraine was getting 104 mcm of gas per day, or 75 per cent of the usual volumes.
"The Ukrainian side has not resumed talks. Naftogaz did not fly in... The issue of debts for gas supplied to Ukraine has not been resolved," Kupriyanov said.
Debt dispute
Gazprom reduced supplies to Ukraine on Monday after saying it had failed to reach a compromise with Naftogaz, Ukraine's national gas company, over a $600 million debt for previous supplies and a deal for deliveries in 2008.
Gazprom has threatened to cut gas supplies during previous pricing disputes with former Soviet neighbours Ukraine and Belarus, but this is only the second time it has acted on the threat after a landmark cut in the New Year of 2006.
That brief disruption reduced supplies to Gazprom's west European customers, making them wary of any hint of a new row.
The new reduction comes as Europe's heating season is nearing its end, unlike in 2006 when it came in the middle of winter.