Lithuania on Monday blasted plans by Russia and Belarus to build nuclear power plants close to its borders, accusing both of lax safety and environmental standards.

Lithuanian Foreign Minister Audronius Azubalis said he was concerned the projects flanking Lithuania in Belarus and Russia's Baltic exclave of Kaliningrad were "bypassing international safety and environmental standards."

"This is not just an issue for Lithuania... it should be a matter of concern to all countries in this region. We should do everything possible to make these two projects develop according to international standards. It is vital," Azubalis said, following talks in Riga with his Latvian counterpart Edgars Rinkevics.

Asked by AFP what proof Lithuania had concerning the safety of the Russian and Belarusian projects, Azubalis said he had yet to receive satisfactory responses to written requests for information through official channels including the International Atomic Energy Agency (IAEA) and Espoo Convention Committee.

"Our questions regarding these nuclear power plant projects have real grounds... I'm not going to explain in detail what's wrong now, but the sites were chosen for these two plants in violation of the International Atomic Energy Agency requirements," Azubalis said.

The Lithuanian foreign ministry provided AFP with a document dated May 4 expressing "deep concern" over an alleged recent accident at Russia's Leningrad NPP-2 nuclear facility, which is still under construction.

"The incident in Leningrad NPP-2 raises a number of serious questions about the safety of this and two other planned (plants) near Lithuanian borders and the capital Vilnius which are projected to be based on the same technology and possibly the same means of construction," the document states.

Latvian Foreign Minister Edgars Rinkevics offered a cautious endorsement of Azubalis' concerns.

"We want to see full transparency," Rinkevics said. "These two nuclear power stations will be very close neighbours and we have a right to expect full cooperation from Russia and Belarus regarding all the necessary environmental protection and safety standards."

Lithuania and Latvia, together with Estonia and Japanese company Hitachi, have putative plans of their own to construct a joint nuclear power plant at Visaginas in northern Lithuania to replace the Soviet-era Ignalina facility which was shut down in 2009.