Prague - Russian natural gas supplies to the Czech Republic dropped by 75 per cent early Tuesday amid the ongoing gas row between Russia and Ukraine, a gas importer said.

Martin Chalupsky, a spokesman for country's leading gas importer and distributor, RWE Transgas, described the drop as "serious" but said that the company is able to meet Czech consumption at the moment.

He said that the firm received all of its contracted gas from Norway and began drawing on its underground reserves in order to keep supplying customers.

The company's underground reserves of 2 billion cubic metres of gas would last for 40 days under current daily consumption of 50 million cubic metres, Chalupsky said.

However, if temperatures were to drop below minus 5 degrees Centigrade, the firm's reserves and Norwegian deliveries would last only for "weeks," company executive Jan Nehoda said.

The company, which commands 71 per cent of the Czech market, currently receives 8 million cubic metres of gas from the Scandinavian state and 5 to 6 million cubic metres from Russia, the executives said.

The Czech Republic relies on Russia for 78 per cent of its gas needs, according to the International Energy Agency data. (dpa)