Measurement stations in Sweden and Denmark registered powerful underwater blasts in areas of Nord Stream gas leaks on Monday, reported Swedish broadcaster SVT on Tuesday, citing the Swedish National Seismic Network.

"There is no doubt that these were explosions," Bjorn Lund, a seismologist from the network, told SVT.

There were two blasts recorded shortly prior to the discovery of the three leaks on the pipelines linking Russia and Europe.

The blasts took place near the location of the gas leaks off the coast of the Danish island of Bornholm, Peter Schmidt, a seismologist from Uppsala University, told AFP.

Russia, which has slashed gas deliveries to Europe after the West imposed sanctions, said sabotage was a possibility and the incident undermined the continent's energy security.

A senior Ukrainian official called it a Russian attack to destabilize Europe, without giving proof, according to a Reuters report.

The Nord Stream pipelines have been flashpoints in an escalating energy war between European capitals and Moscow that has pummeled major Western economies, sent gas prices soaring and sparked a hunt for alternative energy supplies.

(With input from agencies)