Grant Shapps, the MP for Welwyn Hatfield, has been announced as the UK's new defence secretary by the prime minister.

Rishi Sunak has turned to Mr Shapps to replace Ben Wallace, who served as defence secretary from 2019 until his resignation earlier today (Thursday, August 31).

Mr Shapps was spotted entering Number 10 Downing Street shortly before 9am today, with the news being made official around 40 minutes later.

The role of defence secretary has become especially high-profile following Russia's invasion of Ukraine, and today's announcement marks a significant promotion for Mr Shapps.

He posted on X (formerly known as Twitter), writing: "I’m honoured to be appointed as Defence Secretary by Rishi Sunak.

"I’d like to pay tribute to the enormous contribution Ben Wallace has made to UK defence & global security over the last 4 years."

"As I get to work at @DefenceHQ, I am looking forward to working with the brave men and women of our Armed Forces who defend our nation’s security.

"And continuing the UK’s support for Ukraine in their fight against Putin’s barbaric invasion."

The MP for Welwyn Hatfield has now held five Cabinet posts within the last year. He has also served as transport secretary (2019 until October 2022), home secretary (October 2022), business secretary (October 2022 until February 2023), and energy security and net zero secretary (February until August 2023).

He visited Ukraine just last week while serving in the latter role, as the government announced funding to provide fuel for Ukraine's nuclear power plants.

Mr Shapps' predecessor, Mr Wallace, had previously announced his intention to stand down as an MP at the next general election, expected to be held in 2024.

In his letter to the prime minister announcing his resignation, Mr Wallace said: "It has been an honour to serve alongside the men and women of our Armed Forces and intelligence services who sacrifice so much for our security.

"The last four years has seen our Armed Forces and their leadership shine through. Whether it was the evacuation of Kabul, our Covid response, Ukraine or Sudan, the professionalism of our people has been first class.

"As I finish my tenure, I can reflect that the Ministry of Defence that I leave is now more modern, better funded and more confident than the organisation I took over in 2019.

"As well as being active around the world we have also invested in prosperity at home.

"I am proud that I have secured GCAP, AUKUS, NCF, National shipbuilding and the Defence and Security industrial strategies that will secure thousands of British jobs for our young people many years into the future.

"The Ministry of Defence is back on the path to being once again world class with world class people."

Boris Johnson, the former prime minister, reacted to the news with a post on X: "Sad to see departure of my friend Ben Wallace.

"A fine Defence Secretary who got so many calls right - especially on Ukraine. Grant Shapps is an excellent choice to succeed him."

Andrew Lewin, Labour's candidate for Welwyn Hatfield at the next general election, told the Welwyn Hatfield Times: "Congratulations to Grant Shapps on his new role as Defence Secretary.

"Having taken jobs under Cameron, Johnson, Truss and Sunak, nobody is more closely associated with the Conservative record in government over the last 13 years.

"After 13 years, NHS waiting lists are at record highs, the cost of living crisis is deepening and the size of our armed forces has been cut repeatedly.

"I look forward to debating his record in government and setting out the Labour case for change in Welwyn Hatfield and across the country."

Shortly after Mr Shapps' appointment, Claire Coutinho was confirmed as his replacement as energy security and net zero secretary.