WARSAW (Reuters) - Poland’s security agents have detained a government official on suspicion of providing Russia with secrets about tactics Warsaw planned to use to try to block the construction of a gas pipeline, the Polish government said on Monday.

Stanislaw Zaryn, spokesman for the minister responsible for the secret services, told state broadcaster TVP Info that the man had been detained on Friday, and that a court had approved his detention the following day for up to three months.

The official, who has been identified only as Marek W., held a position responsible for energy projects and was providing the Russians with information on how Warsaw intended to block the Nord Stream 2 pipeline, Zaryn said.

Poland opposes the construction of Nord Stream 2, which would connect Russia to Germany through a pipeline across the sea and allow Moscow to pump more gas to its main markets in Western Europe while bypassing states further east.

Warsaw says the pipeline would strengthen Gazprom’s dominant position on the gas market in central and eastern Europe, limit competition and increase Europe’s dependence on Russian gas.

Polish state news agency PAP said the suspect had been in contact with Russian intelligence officers working under diplomatic cover at the Russian embassy in Warsaw.

The case comes as Britain and the European Union have clashed with Moscow, accusing Russia of being involved in the poisoning of a former Russian double agent in England.

The Russian ambassadors to Poland, Latvia, Lithuania and Estonia were summoned to the foreign ministries of those countries on Monday, Russian news agencies reported.

The Russian ambassador in Poland declined to comment on the reason for the meeting at the Polish foreign ministry.