(Adds comments from Fico, importer)
PRAGUE, Oct 1 (Reuters) - Russian gas supplies to Slovakia have been cut by 50 percent, Prime Minister Robert Fico said on Wednesday, the deepest so far in a string of reductions in recent weeks that have affected flows into the central European country.
Fico said he would call a crisis meeting of the cabinet if the reductions persisted but assured customers they would keep receiving unrestricted supplies from the national gas firm SPP.
"Despite the situation, SPP guarantees continuous supplies for all its customers, from households to large companies," Fico told a news conference broadcast live on television.
Gas flows from Russia's Gazprom into several central European countries, including Poland, Romania and Austria, have been cut in the past weeks without clear reasons.
Gazprom had no immediate comment.
"The Russian side talks about technical problems, about the necessity of filling up storage for the winter season," Fico said. "I have used this expression and I will use it again: gas has become a tool in a political fight."
Both Slovakia and Poland have been providing Ukraine with gas supplies through "reverse flow" pipelines after Russia cut supplies to the country in June due to a row over unpaid bills and the conflict in eastern Ukraine.
Fico, when asked whether Slovakia would continue reverse supplies to Ukraine, said Slovakia would meet its commitments. He also said Slovakia could cover its daily needs through reverse flows from the West if needed.
SPP said it made an extraordinary purchase of natural gas on the spot market after experiencing a 50 percent drop in Russian deliveries on Wednesday.
It said the spot purchase was enough to cover the current daily consumption and to inject gas into storage. SPP has 1.5 billion cubic metres of gas stored and will continue to fill storage until the end of October, it said.
Central European spot gas markets rose to over 25 euros per megawatt-hours (MWh), their highest levels since the Ukraine crisis broke out in February/March. (CEE gas price chart: link.reuters.com/ges92w)
SPP said it had adopted measures to make it possible to transmit gas from Russia or other sources through alternative entry points in case supplies through the main point on the Ukrainian border were restricted.
Data from Slovak pipeline operator Eustream showed flows through the Slovak pipeline system, with high-capacity connections to Ukraine, the Czech Republic and Austria, similar as in the previous days. The system serves multiple traders and customers. (Reporting by Jan Lopatka and Michael Kahn, additional reporting by Vladimir Soldatkin in Moscow)