The prime minister believes Brexit has had some benefits, Downing Street has said on the fifth anniversary of the UK leaving the European Union.

A No 10 spokesman pointed to freedom from EU regulations, helping to make the UK a more competitive financial hub.

However, he said Sir Keir Starmer also wanted “to make Brexit work better for the British people” and strengthen relations with Europe.

The Conservatives accused the government of being “determined to dismantle Brexit and drag us back into the EU’s grasp”.

But the Liberal Democrats criticised the Brexit deal struck by the Tories as “an utter disaster for our country” and called for close ties with the EU.

The UK officially left the EU at 11:00 GMT – midnight in Brussels – on 31 January 2020, three-and-a-half years after the the 2016 referendum.

The government has marked the anniversary with little fanfare, with no official events to celebrate the occasion.

Asked why the PM had not said anything specific for the anniversary, Downing Street said the government was “very much looking forward”.

A Number 10 spokesman said: “We know we can do better to make Brexit work for the British people, that it’s in the UK’s national interest to have a more co-operative relationship with the EU.

“They’re our largest trading partner and our closest neighbour, and will be vital in helping us to tackle ongoing threats to our security, and that’s why we’re working together with the EU to strengthen our partnership.”

Asked what benefits Brexit had brought, he said the UK was “no longer bound by EU procurement rules”.

“That is a big benefit for us, as well as our freedom to adapt our financial services regulations to make them more suited to the UK market environment, and that’s enhanced London’s competitiveness as a financial hub,” he added.

Since winning power, Sir Keir, who backed remaining in the EU and once supported a second referendum, has promised to “reset” relations with the 27 nation bloc and secure a better deal with it.

However, he has stressed the UK will not be rejoining the EU or the single market, which enables goods, services and people to move freely between member states who also apply many common rules and standards.

The government has also pledged the UK will not rejoin the customs union – an agreement between EU countries not to charge taxes called tariffs on things coming from outside the bloc.

Over the weekend Sir Keir will host German Chancellor Olaf Scholz, before attending a meeting of EU leaders in Brussels on Monday.

Conservative leader Kemi Badenoch called Brexit “the greatest vote of confidence in our country”, but said there was “still a lot more to do”.

She said a trade deal with the United States would be a “Brexit opportunity we need to take”.

Nigel Farage, one of the key figures behind the Brexit campaign, said it had been a success constitutionally and in terms of foreign policy but admitted many who voted to leave would say “it’s been a huge disappointment”.

The Reform UK leader said huge numbers voted for Brexit to cut immigration but the figures had gone up, which he blamed on the previous Conservative government.

He rejected the idea the public had been misled about the benefits of Brexit, and claimed that if he had been in charge immigration would have gone down.

Former chief Brexit negotiator Lord Frost told BBC Radio 4’s Broadcasting House Sir Keir wanted to “inch us back into the orbit [of the bloc] by stealth”, with rules on food standards and other areas set in Brussels.

The Tory peer argued the current Brexit deal was working well and it was not necessary to start “tearing bits of it up again”.

Liberal Democrat leader Sir Ed Davey used the anniversary to reiterate his call for a UK-EU customs union deal, saying it would “unlock growth, demonstrate British leadership and give us the best possible hand to play against President Trump”.

Green MP Ellie Chowns also called for the UK to rejoin the customs union and agree a youth mobility scheme with the bloc, which would make it easier for young people to study and work in the EU.

She added that “full membership of the EU remains the best option for the UK” and said her party would pursue “a policy to re-join as soon as the political will is present”.

The full interview with Lord Frost will be on BBC Radio 4’s Broadcasting House from 09:00 GMT on Sunday