Beijing: The Chinese education ministry says Australia is denying visas to Chinese PhD students even though they have been offered places with Australian universities.

In comments to Fairfax Media, the Chinese education ministry spokesman said Chinese students had not only faced delays in visa processing in recent times, but "some students failed to obtain visas, even after review, causing inconvenience to both applicants and Australian schools".

A tour guide takes a group of Chinese people for a tour of Sydney University in February. Credit:Fairfax Media

The delays in processing visas for the PhD students as the Home Affairs department conducts national security checks has emerged as the latest point of diplomatic tension between Australia and China.

Some Chinese students have been waiting more than eight months for security checks, which are conducted by ASIO, and are unable to take up offers from Australian universities as they wait.