Tanzanians are mourning veteran politician and former Speaker of Parliament Job Ndugai, who became the first to resign from the role after a public fallout with the president.

Ndugai, who has served as an MP for the past 25 years, died in Dodoma, Tanzania's capital, on Wednesday at the age of 62, Speaker Tulia Ackson announced.

The cause of death was not given, although local media reported he had been undergoing treatment at a hospital in the city.

In a statement, President Samia Suluhu Hassan has said she "received with sorrow" the news of Ndugai's death, and has sent condolences to his family and friends.

Ndugai has been an MP since 2000 and was preparing to defend his Kongwa parliamentary seat in Dodoma in the October general elections, having just won the nomination of the ruling CCM party.

"We have lost a courageous leader, a true patriot and a capable public servant who made a significant contribution to strengthening the institution of parliament," CCM said in its condolence message.

Early in his political career, Ndugai was named the most active MP in parliament, and became deputy speaker in 2010, serving until 2015 when he was elected speaker.

He resigned in 2022 following controversial remarks he made about Tanzania's borrowing and national debt, which drew criticism from President Samia.

He had warned against mounting debt levels saying it risked the country being "auctioned".

He later apologised, saying "I was wrong - gravely wrong. May God forgive me. Forgive me, Tanzanians," in the wake of strong reactions and a backlash against him from government and the ruling party.

Ndugai's comments were seen as uncharacteristic of a man known for his unwavering loyalty to the ruling party.

He had often faced criticism for appearing overly compliant with the government at the expense of parliamentary independence.

At one point, some analysts criticised him for presiding over what they considered the weakest parliament between 2015 and 2020, during President John Magufuli's first administration. He dismissed the criticism, telling a local publication that those faulting him did not understand parliamentary democracy.

He was also criticised when he announced that Magufuli would run for president beyond the two constitutionally permitted terms.

He had also said he had the power to prevent any MP from speaking in parliament.

Besides that, Ndugai faced stinging criticism for making dismissive remarks about opposition MP Tundu Lissu, who was recovering in hospital after surviving an assassination attempt in which he was shot multiple times.

He also presided over the controversial stripping of Lissu from his parliamentary seat, citing his prolonged absence and failure to submit wealth declaration forms.

Critics and opposition members described this as "insensitive" and "inhumane", as Lissu was said to be still recovering abroad rom his injuries.

This was a far cry from his earlier political years - when he ran for speaker in 2015, he was reportedly the only candidate backed by both CCM and opposition MPs.

So it was unsurprising that when he made his remarks criticising government borrowing, there was little support from even within his own party.

Still, after he resigned, which he said was in the interest of the nation, he remained a loyal and influential ruling party figure until his death.

Plans for his funeral are ongoing and further information will be released later, parliament said.