Ukrainian officials held emergency talks in Moscow yesterday after Kremlin-controlled Gazprom threatened to cut gas supplies to Ukraine on Monday, sending a shiver through EU nations that suffered fuel shortages during a similar row in 2006.

Gazprom accused Ukraine of owing $1.5 billion (€1 billion) in unpaid gas bills, cranking up tension as Ukraine's leaders prepare to visit Moscow for talks on a new energy deal and Russia rails against Kiev's bid to draw closer to the EU and Nato.

"If the Ukrainian side does not settle the problem on Monday, Gazprom will have to stop supplies of Russian gas to Ukraine," said Gazprom spokesman Sergei Kupriyanov. "All our partners follow payments' schedules and it is only Ukraine that . . . gets the gas it needs, but does not pay for it." Both Moscow and Kiev have reassured the EU that its members will not suffer any fuel disruption if Gazprom does cut supplies to Ukraine.

A similar price dispute in January 2006 caused supply shortages in several central and southern European countries who receive gas via Ukraine. Most of the gas Ukraine buys from Gazprom comes from the state of Turkmenistan, and a relatively small amount arrives directly from Russia. This Russian gas would be turned off if the debt row is not resolved.

Ukraine denies owing money to Gazprom and blames the row on RosUkrEnergo, an opaque transit firm that handles Gazprom's deliveries of gas from Turkmenistan to Ukraine. Ukraine's new prime minister Yulia Tymoshenko has vowed to overhaul her country's gas agreement with Russia and exclude RosUkrEnergo from the deal. Many commentators have noted the timing of the recent arrest of alleged mafia boss Semyon Mogilevich, who is often accused of being behind RosUkrEnergo.

Ukrainian newspapers accuse Russia of trying to extract political concessions from Ukraine in return for a new gas agreement, including a Kiev pledge not to join Nato and to extend the Russian navy's lease on a key base on Ukraine's Black Sea coast.