The UK has failed to improve upon its record low ranking in a closely watched annual league table of international corruption, prompting concern about the “humiliating” result.

The UK is still seen as being among the 20 least corrupt nations in the world, according to the annual corruption perceptions index (CPI) produced by campaign group Transparency International.

But the UK’s position of 20th in the world is still significantly lower than in previous years, when Britain consistently ranked in the top 10.

Transparency International cited factors including the Partygate scandal and revelations about large donations to political parties, while one MP referred to the lingering reputational effect of revelations about PPE contracts during the Covid-19 pandemic.

The index is compiled by surveying experts and business leaders, asking them to score and rank countries by the perceived level of corruption in their public sectors.

Denmark tops the rankings, followed by Finland and Singapore. The average score is 43 on a range of 0 to 100, where higher numbers indicate the highest standards of anti-corruption.

The UK scored 71, its lowest result since the index was launched in 2012.

The Labour MP Phil Brickell, a member of a cross-party parliamentary group (APPG) examining corruption, described the UK’s position on the fringe of the top 20 as “humiliating”.

“Whether it’s cracking down on corporate secrecy in UK offshore jurisdictions, ending London’s role as a favourite destination for every crook and kleptocrat looking to hide their assets, or simply cleaning up our own politics by reforming rules around donations and second jobs, the time to act is now.”

Brickell referred to claims of corruption around Covid contracts and revelations about MPs profiting from second jobs among reasons that the perception of the UK, reflected in the index, may have worsened.

Transparency International collected the data for the index between January 2022 and September 2024, a period it said included several events that may have dented trust in British politics.

It cited revelations about major donors funding British political parties in the run-up to the election, as well as the resignation of Boris Johnson as prime minister, after an investigation into whether he had misled parliament over the Partygate scandal.

The Guardian has approached the Conservative party for comment.

The campaign group called for measures including the removal of big money from UK politics, greater transparency over political lobbying and tighter controls on transparency around appointments accepted by members of the House of Lords.

Daniel Bruce, the chief executive of Transparency International, said: “Unless we act decisively to strengthen anti-corruption frameworks globally, we risk seeing further democratic backsliding and weakening of the international response to the critical challenges we face.

“The UK government ought to play a pivotal and much-needed role by taking the corrupting influence of big money out of politics, delivering on commitments to protect the integrity of government and accelerating efforts to tackle corruption globally.”