UPDATE 1-Russia rejects U.S. conditions, sees 'minimal' chance of extend New START nuclear arms deal

* Russia-U.S. nuclear arms control pact expires in Feb.

* Washington says agreement needed before Nov. elections

* U.S. insists China needs to be involved

* Russia says China should decide for its own

* (Adds detail, quotes)

By Gabrielle Tétrault-Farber

MOSCOW, Sept 21 (Reuters) - Russia sees "minimal" chances of extending the New START treaty with the United States - the last major nuclear arms pact between the two countries - because it does not accept conditions set out by Washington, Deputy Foreign Minister Sergei Ryabkov was quoted as saying on Monday.

His comments came after Marshall Billingslea, the U.S. Special Presidential Envoy for Arms Control, told a Russian newspaper that Moscow must accept a joint agreement with the United States on extending the treaty before the U.S. presidential election in November.

"I suspect that after President Trump wins re-election, if Russia has not taken up our offer, that the price of admission, as we would say in the U.S., goes up," Billingslea told Kommersant newspaper in an interview.

Ryabkov said the condition stated by Billingslea constituted an ultimatum and lowered the chances of reaching any kind of agreement to extend the deal, which expires in February next year.

"We cannot talk in this manner," TASS news agency quoted Ryabkov as saying. Another agency, RIA, quoted him as saying the chances of a treaty extension were minimal.

The New START accord, signed in 2010, limits the number of strategic nuclear warheads that Russia and the United States can deploy.

Failure to extend it would remove the main pillar maintaining the balance of nuclear arms between the two countries, adding yet another element of tension to their already fraught relationship. (Additional reporting by Maria Kiselyova and Tom Balmforth; Writing by Gabrielle Tétrault-Farber; Editing by Mark Trevelyan)