SYDNEY - Russia has reacted angrily to an Australian decision to deny visas for members of its space agency to attend a satellite conference which began in Queensland on Tuesday.

The Russian ambassador to Australia claimed it was an "unfriendly" act by Australia, while organizers of the three-day symposium said they were not sure the delegates were not granted visas.

Hundreds of delegates arrived at the Gold Coast for the symposium hosted by the International Global Navigation Satellite Systems Society.

But the Australian Broadcasting Corporation (ABC) reported several members of Russia's space agency -- Roscosmos -- who were invited were denied their visas.

Russian embassy spokesman Alexander Odoevskiy told the ABC his country was disappointed.

"Obviously every country can decide who to let (have) a visa but in the current circumstances, given it's an international - as I understand United Nations conference - it is not a very friendly step from Australia as a whole country to do so," he said.

Odoevskiy said he did not know if espionage fears were behind the visa decisions.

"I, frankly speaking, don't know because we are not intelligence so I wouldn't comment on this but I understand that ( under) international circumstances this is not the idea of a conference, an expert panel conference to be used for spying," Odoevskiy said.

The Australian Department of Immigration and the immigration minister have not commented.