World Bulletin/ News Desk
"Today at 10:05 Ukraine started taking Russian gas through Sudzha (compressor station). Now we are building up the volumes of deliveries on all routes to reach normal operation," Gazprom spokesman Sergei Kupriyanov told Reuters.
A spokeswoman for UkrTransGaz, a unit of Ukrainian state energy firm Naftogaz, also confirmed it had started receiving Russian gas for transit.
Gazprom Chief Executive Alexei Miller had said earlier that under the new contract Ukraine would pay $360 per 1,000 cubic metres of gas in the first quarter of this year, a sharp rise on the $179.5 that Kiev was paying for Russian gas last year.
Officials have said it would take 36 hours after the restart for the pipeline system to become operational again and for gas to reach Europe, parts of which have had to ration supplies to households and businesses because of the dispute.
Austrian oil and gas group OMV said Russian gas could arrive at its hub in Baumgarten, in the east of the country, on Wednesday.
"OMV is in touch with Gazprom and the network operators and is prepared for the start of supplies," the company said in a statement.
The European Union, which tried with growing frustration over the past two weeks to broker a deal, said it would not consider the crisis over until its monitors verified that gas had reached the bloc.
Russia provides about a quarter of Europe's gas requirements and pumps 80 percent of this via Ukraine.
Russia and Ukraine signed a 10-year deal on Monday to renew supplies of Russian gas to Ukraine and Europe with a ceremony.
Ukrainian Prime Minister Yulia Tymoshenko and Russian Primer Vladimir Putin attended the ceremony. Putin also said intermediaries would be removed from gas trade with Ukraine.
Gazprom cut the natural gas flow to Ukraine at the beginning of this year after dispute with this country over natural gas prices.
Many southeast Europe countries had announced there was decline in the flow of natural gas through their pipelines.