Czech President Milos Zeman is being criticized for refusing to grant a university professorship — the nation's top academic title — to a critic of his, allegedly because the man is also a gay rights activist.

Zeman has refused to fully explain his stance, saying he doesn't want to "humiliate" the candidate, Martin C. Putna, "by naming the reasons publicly."

But over the weekend Zeman said on Czech public TV that he "does not recognize people aspiring to teach at universities" who attend gay festivals.

On Monday, Zeman said Putna's sexual orientation itself is not an issue. Putna had backed Zeman's opponent in the last presidential election.

Czech presidents formally appoint the country's university professors.

Politicians and universities have said Zeman's remark was an unacceptable intrusion on academic rights.