Russia's gas monopoly OAO Gazprom (GAZP.RS) said Tuesday Ukraine's state natural gas company Naftogaz has submitted full payment for June deliveries.
"This is positive, but expected, given a low volume of gas bought in June, which averaged 33 million cubic meters a day," Gazprom spokesman Sergey Kupriyanov said.
The company said, however, that Naftogaz may have problems with July payments as deliveries to Ukraine during the month are to be significantly higher than in June.
Ukraine's outspoken Prime-Minister Yulia Tymoshenko said Tuesday that while she holds the post, "there would be no return of the shameful practice of nonpayment for gas," and that Ukraine will be paying in full in the future.
However, Gazprom is worried by the increased volume of gas, ordered by Ukraine for July.
"Ukraine has raised its order to 120 million cubic meters a day for July," Gazprom's Kupriyanov said.
He added that a lion share of that gas is not sold to consumers, but pumped into underground storages, which makes the payment in August "a threshold for Naftogaz" and for European countries, as there is "still no solution of the joint financing of Naftogaz's activity, on which Russian side insists."
Ukraine is seeking a loan to pay for the gas, but no final decision has been made either by the E.U., or by international financial institutions.
"The European Commission continues to work with international financial institutions, Ukraine and Russia to provide a sustainable solution for payments," Mark Gray, spokesman for European Commission said Tuesday.
He added that Ukraine urgently needs to undertake reforms to its gas sector, and that the Commission has decided to convene a further meeting at technical level at the earliest opportunity with representatives of Russia and Ukraine.
Naftogaz stores gas during warm period of the year in order to use it during winter, when demand for it picks.
Gas stores for the upcoming winter season are the lowest within a 10-year period, according to Naftogaz.
The company plans to pump 7.6 billion cubic meters of gas into its stoppages in by October.