Ottawa, capital of Canada, has apparently refused to grant visas to Russia and Chinese delegates at a prestigious international astronautical conference on Monday. The refusal has not only surprised heads of Russian, Chinese space agency, but head of Canada's space agency too.

The delegates of Chinese and Russian space agencies were conspicuous by their absence in the conference, asking questions from among a number of participants.

Past president of the International Astronautical Federation, Berndt Feuerbacher, had moderated the opening plenary session.

According to Feuerbacher, Russia and Chinese delegates were foreseen to be in prestigious international astronautical conference as they have also attended the conference in the past. Feuerbacher also said that the heads of the two space agencies will be in the session in future.

Feuerbacher said, "It is just unfortunate, due to problems especially in the visa area, that we couldn't have these delegations here. I apologize for this".

The issue has come in the middle of delegate-level talk about international co-operation's importance in the space-exploration field. A Russian capsule had brought home Canadian astronaut Chris Hadfield. But the country has drawn the wrath of countries for its aggression against Ukraine.

According to Feuerbacher, it is not possible to have to a successful talk about global space co-operation without nations like China and Russia. He said that this not Canadian space agency's intention.

Head of the Canadian Space Agency Walter Natynczyk said that he could not explain what had gone wrong in the process of planning a conference. According to him, he had seen the visa problem only in the past couple of days.

A spokesman of Citizenship and Immigration Canada has cited some privacy laws in refusing to discuss whether Russia and Chinese delegates have been refused visa to attend the conference.