Labour has demanded Boris Johnson “stop stalling” and introduce a long-delayed register of foreign owners of properties within weeks.
David Cameron first announced plans for a register in 2016 and the overseas entities bill was published in 2018.
The government said it would “ensure there is no safe space for illicit money in our society”.
But the legislation, designed to reveal the true owners of property and other assets, has yet to be brought to parliament.
The National Crime Agency has said money laundering costs the UK more than £100bn pounds a year.
Shadow Treasury minister James Murray said the prime minister and Rishi Sunak must introduce the legislation by December 10.
In a letter to Lucy Frazer, the financial secretary to the Treasury, seen by HuffPost UK, Murray said: “The prime minister and chancellor must stop stalling on this vital legislation to provide transparency that had been promised but has not been delivered.
“A lack of transparency and troubling cronyism have been revealed as the hallmark of this Conservative government.
“The truth is that concerns over Russian donations to the Conservative Party, and concerns over the use of high-end property in the UK for Russian money laundering, means that putting in place the register of overseas owners without delay is a key part of restoring the trust in politics that your colleagues have done so much to erode.”
He added: “The government should bring forward this legislation by no later than December 10, 2021, the fourth anniversary of the UK anti-corruption strategy.”
The 2017 anti-corruption strategy included a commitment to bring forward legislation in that session of parliament.
In 2019, when Theresa May was prime minister, the government told parliament it would “deliver an operational register in 2021”.
But Labour said since Johnson took office in the government had repeatedly watered down that commitment and in its last legally required update on progress, “no mention” of a date had been made.
In the Commons earlier this month, a Treasury minister refused to say when the legislation would be introduced, simply saying they would write to Labour on the matter.
It comes amid the ongoing row over sleaze in Westminster, including the revelations that former attorney general Geoffrey Cox has been giving legal advice to British Virgin Islands (BVI), a tax haven, as it fights allegations of corruption made by the UK Foreign Office.