Candidates for one of the most prestigious posts in poetry are embroiled in a war of words as Nobel laureate Wole Soyinka hit back at claims by broadcaster Melvyn Bragg that he was too old and “grand” for the role at Oxford University.

Bragg, who had previously backed the Nigerian poet to be the next Oxford chair of poetry, told The Sunday Times he was switching his allegiance to Simon Armitage, saying he was concerned 80-year-old Soyinka would not “bother to come to Oxford” were he appointed. “Soyinka is a grand man … I also query his age,” Bragg said.

Soyinka, a prolific poet, novelist and playwright as well as a political activist, said he was confounded by the comments.

“How curious that anyone would even speculate that I would allow busy and committed people - friends, colleagues and total strangers - to waste their time nominating and campaigning on my behalf for such a prestigious position if I were not serious about contesting,” he said.

Soyinka has been nominated by an impressive number of graduates, 149 in total, with Armitage collecting 54 nominations, including the literary critic John Carey, now emeritus professor of English at Oxford. All Oxford graduates are able to vote for the position, with polling set to begin on Friday.

The post is exceptionally prestigious, with the holder expected to give three lectures a year. The only qualification is “that candidates be of sufficient distinction to be able to fulfil the duties of the post”.

Previous chairs have included Seamus Heaney, Matthew Arnold, WH Auden and Robert Graves. Arnold was the first incumbent to deliver his lectures in English rather than Latin.

Soyinka’s personal representative for the campaign, Lucy Newlyn, a poet and professor of English at Oxford, said his decision not to submit a statement for the post was in no way unusual for a would-be poetry professor, and nor was his advanced age.

“Geoffrey Hill, the current professor of poetry, did not submit a statement,” Newlyn said. “He, like Soyinka, is over 80, and his tenure has been a great success.

“Soyinka is a candidate of absolutely outstanding distinction, energy and enthusiasm. If elected, he will be totally committed to the post. Candidates are permitted to submit statements if they wish, but this is entirely optional.”

Addressing the issue, Soyinka said: “Opting not to make a ‘statement of intent’ is probably the result of a hangover from recent Nigerian elections – nothing more sinister!”

Ken Macdonald QC, the warden of Wadham College and one of Soyinka’s key backers, said: “Wole Soyinka is a poet and activist of world standing who has faced persecution and suffering with surpassing dignity. He is that rare thing: a great writer whose life and eloquence have come together in a valiant struggle for rights and freedom. His election would grace the University of Oxford."

Soyinka’s candidacy has been endorsed by a number of high-profile graduates, including the director of Liberty, Shami Chakrabarti. “Pursued and repeatedly imprisoned by dictators who feared him, his shining language of resistance has never dimmed and his sense of justice never faltered,” Chakrabarti said. “His appointment would bring honour to the University of Oxford.”

The former archbishop of Canterbury Rowan Williams has also endorsed Soyinka, calling him “a massive cultural presence”.

Seamus Perry, head of the university’s English department, said there was “no compulsion” for any candidate to submit a statement.

“The university made it clear that candidates are very welcome to do so only if they wished to,” he said. “If a candidate has agreed to be nominated for the professorship, the university naturally takes as read his or her full readiness to carry out the various duties of the post.”

Soyinka’s backers have been keen to stress that they consider the post more like an honour to be bestowed than a job to be applied for and where a statement of intent would be expected.

The result of this year’s vote is expected to be announced on 19 June, with three other candidates in the running: Ian Gregson, Seán Haldane and A E Stallings. The winning poet will succeed Hill in October 2015.