Theresa May gave the “rubber stamp” to Tristram Hunt’s appointment as the director of the Victoria and Albert Museum in London, a spokesperson for the Prime Minister has confirmed.

It transpired Ms May had signed off the former shadow Education Secretary’s new appointment on Thursday – the day before he publicly announced his resignation as the Labour MP for the Stoke-on-Trent Central constituency.

At a briefing a spokesman for the Prime Minister said the V&A appointment is a “very carefully controlled, tender process” and “the decision will be rubber stamped, or is rubber stamped by the Prime Minister”.

They refused to add any further details but the Department for Culture, Media and Sport later confirmed Ms May had approved Mr Hunt’s role on Thursday. Culture Secretary Karen Bradley had earlier congratulated Mr Hunt, adding: “I look forward to working alongside him”.

However, it raises the question of whether the Prime Minister was aware that a crucial by-election would take place before Jeremy Corbyn, the Labour leader, had been notified of Mr Hunt’s imminent departure.

In a statement Mr Corbyn added: “I would like to thank Tristram Hunt for his service to the people of Stoke-on-Trent Central and to the Labour Party. I wish him well in his future role at the V&A.”

The exit of Mr Hunt is the second within weeks, after Jamie Reed, the MP for Copeland, in Cumbria, said he was also standing down – triggering two perilous by-elections. In his resignation letter, Mr Hunt did not criticise Mr Corbyn, but said the opportunity to lead the V&A was too good to turn down.

“I have no desire to rock the boat now and anyone who interprets my decision to leave in that way is just plain wrong,” he wrote.

Mr Hunt was among many centrist Labour MPs who had refused to serve on Jeremy Corbyn’s frontbench, making his opposition to the leader’s project well-known.

At the 2015 election, he won the Stoke-on-Trent Central seat with a 5,100 majority from Ukip, making the by-election a huge opportunity for that party.

On paper, it is a reasonably safe Labour seat – but Stoke-on-Trent voted 69 per cent to Leave the EU in the referendum, by 81,000 votes to 36,000.

Announcing the appointment, V&A Chairman Nicholas Coleridge said: “On behalf of the Trustees, I am delighted to announce the appointment of Dr Tristram Hunt as Director of the Victoria and Albert Museum.