Breaking News Emails

Get breaking news alerts and special reports. The news and stories that matter, delivered weekday mornings.
 / Updated 

MOSCOW - Russia on Monday said it would cut off gas supplies to Ukraine as a payment deadline passed and negotiators failed to reach a deal on gas prices and unpaid bills.

Gazprom's spokesman Sergei Kupriyanov said that since Ukraine had paid nothing for the gas by Monday Moscow has no legal grounds to supply it to Ukraine any more.

"Gazprom supplies to Ukraine only the amount that has been paid for, and the amount that has been paid for is zero," Kupriyanov said Monday morning.

Sign up for breaking news alerts from NBC News

Kupriyanov added that the supply to Europe will continue as planned and Ukraine has the obligation to make sure the gas will reach European customers.

Gazprom said in a statement, however, that it had notified the European Commission of "a possible disruption in the gas transit" in case Ukraine decides to siphon off the gas.

A worker turns a valve at an underground gas storage facility near Striy in western Ukraine on May 21, 2014 file photo.GLEB GARANICH / Reuters, file

Cash-strapped Ukraine has been chronically behind on payments for the gas needed to heat homes and fuel its industries.

Gazprom offered the previous president, Viktor Yanukovych, a discounted price of $268.50 per thousand cubic meters after he backed out of an economic and political agreement with the European Union opposed by Russian President Vladimir Putin.

That price was cancelled April 1 and raised to $485 per thousand cubic meters. Russia has now offered $385, but Ukraine insists on the old discounted price. Gazprom has tolerated the late payments but now says Ukraine owes a total of $4.458 billion for gas from last year and this year.

Russian wanted a payment of $1.95 billion for past due bills by 9 a.m. Kiev time Monday. As the deadline passed Gazprom issued a statement that it would start demanding payment in advance for gas.

Ukraine's overall debt to Gazprom is $4.5 billion, the company said on Monday.

The European Commission said in a statement that Ukraine was ready to accept a compromise in talks in Kiev of paying $1 billion now and more later, but Russia was not.

- The Associated Press