UPDATE 1-Gazprom sends warning to Ukraine as deadline looms

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MOSCOW, Feb 28 (Reuters) - Russia said on Thursday it was still committed to reducing supplies to Ukraine from March 3 in a debt and supply dispute, a deadline that falls the morning after Russia's presidential elections.

Russia's gas export monopoly Gazprom (GAZP.MM: Quote, Profile, Research) has often threatened to cut gas supplies during disputes over price with former Soviet neighbours Ukraine and Belarus, but has never made good on the threats except in the New Year of 2006.

That brief disruption cut supplies to Gazprom's west European customers, making them wary of any hint of any new row. A quarter of Europe's gas supplies pass through Ukraine.

Gazprom's chairman, First Deputy Prime Minister Dmitry Medvedev, is heavily favoured to win the presidential election, The gas giant said its insistence that Kiev pay arrears and sign a new supply deal or face reduced deliveries remained in force.

Ukrainian officials say the debt has been paid in full.

"The deadline is in force. No one has cancelled it and we plan to reduce supplies on March 3 if the problems are not solved," Gazprom spokesman Sergei Kupriyanov told Reuters.

Gazprom threatens to reduce supplies to Ukraine by 25 percent. Both Moscow and Kiev have promised supplies to Europe will be unaffected.

"For Ukraine to avoid a supply reduction, we need to clinch an agreement on cooperation in the gas sphere, which has all the necessary elements such as debts and supply volumes," he said, adding he was unaware of any Ukrainian delegation travelling to Russia any time soon.