Imran Khan has told Britain he will retrieve wealth looted from his country and stashed in the UK by corrupt Pakistani politicians.
The former cricketer used his first meeting with British officials since his general election win to say he would pursue laundered money.
New anti-corruption UK legislation designed to target oligarchs and international crime could be used to freeze or seize property and assets if there is evidence it was bought with illegal or unexplained wealth.
Attacks on the greed of Pakistan’s dynastic ruling elite have been the cornerstone of the populist anti-corruption drive which has swept Mr Khan to power.
He has denounced the political class for siphoning off money from public sector institutions and contracts and then salting it away overseas.
The issue has dominated Pakistan’s politics since the Panama Papers leak linked former prime minister Nawaz Sharif’s family to offshore companies and four Park Lane flats.
Sharif was ousted from power, then jailed for 10 years after a court found he was unable to explain how he bought the flats now worth an estimated £8m.
In the meeting with the High Commissioner, Thomas Drew, Mr Khan said it was “our firm resolve to bring back to the country the money laundered to the UK.”
The Telegraph understands no specific requests for investigations or seizures were made during the meeting, but on Thursday the UK said it would “work constructively” with the new leader.
The Government has brought in new legislation to combat money laundering and corruption as it tries to tackle London’s reputation as a haven for dirty money, much of it from Russia.
Expensive London property bought through shell companies in weakly regulated jurisdictions has long been a favourite way to hide ill-gotten wealth for everyone from mobsters to kleptocrats.
A spokesman for the British High Commission said: “Tackling corruption is a UK government priority and we will continue to work constructively with Pakistan on this issue.”
He said Britain has robust laws “for the recovery of illicit assets where there is evidence to do so”.
The meeting also discussed British aid to the country.
Mr Khan’s party back-pedalled on suggestions he would invite foreign dignitaries and international sports stars to his inauguration later this month.
Officials in his Pakistan Tehreek-i-Insaf (PTI) party had earlier in the week met with foreign ministry officials to discuss inviting foreign leaders including Indian Prime Minister Narendra Modi. Invitations to friends from Mr Khan’s cricketing days were also mooted, including Kapil Dev and Sunil Gavaskar.
On Thursday the PTI said Mr Khan had instead decided “to arrange the oath-taking event with austerity” with no foreign dignitaries or celebrities.
A spokesman said: “Being the custodians of tax-payers money, we are looking forward to hold a simple and austere oath-taking ceremony completely national in its façade and essence”,
Meanwhile reports that a computerised anti-fraud system for compiling election night results had been deliberately not used led to calls for an investigation by defeated parties who have alleged Mr Khan won through massive rigging.