A Tanzanian opposition MP has been handed a five-month prison sentence after being found guilty of defaming President John Magufuli.

Joseph Mbilinyi - popularly known as Sugu - from the opposition Chadema party, was convicted by a magistrate's court in the southwestern town of Mbeya.

His co-accused, Emmanuel Masonga, was handed a similar prison sentence.

The two were accused of committing "hate speech" against President Magufuli at Mwenge Primary School in Mbeya on 30 December last year.

Mbilinyi earlier urged his supporters to remain calm and accept any form of court judgment.

Observers say the ruling will deepen concerns that Magufuli's intolerance of dissent is eroding Tanzanian democracy.