Rishi Sunak has said the Conservatives should “learn the lessons” of their general election defeat and “reflect” on their time in government as their conference gets under way.

Mr Sunak described this year as a “difficult one” for the party as “too many good Conservatives have lost their seats”, in a piece for The House magazine.

He said he “will always be sorry” that “he could not deliver the results that everyone’s efforts deserved”, in the article at the start of his final conference as leader.

Rishi Sunak with his wife Akshata Murty arriving in Birmingham on the eve of the Conservative Party annual conference (Stefan Rousseau/PA)

The contest to replace Mr Sunak will feature prominently at the gathering in Birmingham as Robert Jenrick, Tom Tugendhat, Kemi Badenoch and James Cleverly are all vying for the leadership.

Writing in the magazine, Mr Sunak described the conference as “important moment for our party”.

He added: “This is our first conference in opposition since 2009. Of course, we need to learn the lessons of our defeat: we did not get everything right in government – no government ever does – and we do now need to reflect on that. But we should not forget what we have achieved since 2010.”

Mr Sunak announced he would be standing down as the party leader following the election defeat in July.

The winner of the leadership contest is due to be announced at the start of November.

Mr Sunak said it was now the Tories’ “duty to fulfil our role as the official opposition professionally and effectively” pointing to their opposition to the winter fuel payment cut, and holding the government to account on taxation.

He went on: “This will be my last conference as leader, and I want to thank everyone in the party for their support.

“I will always be sorry that I could not deliver the results that everyone’s efforts deserved, but I will always be grateful for everyone’s hard work and commitment.”