Russian President Vladimir Putin outlined to Italian Prime Minister Mario Draghi a system for paying for Russian gas in roubles during a phone call between the two leaders on Wednesday, Draghi’s office said.

Russia has said that, because of Western financial sanctions over Ukraine, it plans to require payment for its energy exports in roubles rather than the usual euros or dollars.

Italy is heavily dependent on Russian gas, and Draghi had previously rejected this. The statement from his office did not say what his response was to Putin’s description of how it would work.

“The conversation centered on the negotiations between Russia and Ukraine and their latest developments,” the statement said. It was the first such telephone conversation between Draghi and Putin since Russia’s invasion of its neighbour on Feb. 24.

Draghi “underlined the importance of establishing a ceasefire as soon as possible,” his office said, adding that the two leaders agreed it was a good idea to remain in contact.

President Vladimir Putin said on Thursday that he had signed a decree saying foreign buyers must pay in roubles for Russian gas from April 1, and contracts would be halted if these payments were not made.

“In order to purchase Russian natural gas, they must open rouble accounts in Russian banks. It is from these accounts that payments will be made for gas delivered starting from tomorrow,” Putin said.

“If such payments are not made, we will consider this a default on the part of buyers, with all the ensuing consequences. Nobody sells us anything for free, and we are not going to do charity either – that is, existing contracts will be stopped.”