The Bangladesh Financial Intelligence Unit (BFIU), which investigates money laundering and suspicious transactions, wrote to the country’s main banks on Tuesday asking them to provide account details for Siddiq and seven of her family members. 

Officials also asked for the bank account details of Siddiq’s aunt, Sheikh Hasina, who was deposed as Bangladesh’s prime minister last year after widespread protests against her rule.

Siddiq’s mother, her sister and her brother were also named in the request, which has been seen by the Guardian.

Bangladesh’s anti-corruption commission has begun an investigation into whether Siddiq, a close ally of the UK prime minister, Keir Starmer, helped embezzle billions of pounds as part of a deal for a Russian-funded nuclear power plant.

Siddiq was pictured alongside her aunt and the Russian president, Vladimir Putin, in 2013 but has denied allegations that she helped broker a deal with Moscow to build the project.

A spokesperson for Siddiq said: “No evidence has been presented for these allegations. Tulip has not been contacted by anyone on the matter and totally refutes the claims.”

Allies say she holds only UK bank accounts, but could not say if that had always been the case.

However, Bangladeshi officials confirmed they had issued a directive to all of the country’s banks and financial institutions to share the account information and transaction details of the seven family members and their associated businesses.

Siddiq, 42, has been under pressure for several weeks over claims about her links to the former Bangladeshi government.

On Monday she referred herself to the ministerial standards watchdog after it was alleged she had lived in properties in London that had been paid for by people tied to her aunt’s party.

She told Laurie Magnus, the prime minister’s independent adviser on ministerial interests: “In recent weeks I have been the subject of media reporting, much of it inaccurate, about my financial affairs and my family’s links to the former government of Bangladesh.

“I am clear that I have done nothing wrong. However, for the avoidance of doubt, I would like you to independently establish the facts about these matters.”

Last week it was revealed that a flat she owns in King’s Cross, central London, was paid for by Abdul Motalif, a developer with links to members of Hasina’s party, the Awami League. Siddiq took ownership of that property in 2004 without paying for it.

Over the weekend it was also reported that she had lived in a property in Hampstead that was paid for by Moin Ghani, a lawyer who represented Hasina’s government, and transferred to Siddiq’s sister.

Siddiq is renting a £2.1m home in East Finchley owned by Abdul Karim, an executive member of the UK wing of the Awami League.

Downing Street has continued to back Siddiq, whose Hampstead and Highgate constituency in north London borders Starmer’s own.

A No 10 spokesperson said on Tuesday: “[Siddiq] is clear that she’s done nothing wrong. However, for the avoidance of doubt, she would like the independent adviser to independently establish the facts about these matters.

“Clearly, it will be up to the independent adviser now to take forward the fact finding and determine what information he needs, and we’ll provide an update at the end of that.”

Magnus could also investigate whether Siddiq misled journalists at the Mail on Sunday by denying that the King’s Cross flat had been bought by Motalif, claiming instead it had been given to her by her parents. A No 10 spokesperson said the adviser would be able to set the scope of his own inquiries.

Hasina came to power in 2009, with her regime later facing accusations of authoritarianism, human rights abuses and corruption. She resigned and fled the country last year after days of protests led by student activists, in which hundreds of people died.

The Observer revealed in November that Bangladeshi investigators believe a handful of powerful families and businesses linked to the Awami League party acquired billions of pounds by illicit means and siphoned the money out of the country.

Siddiq has previously denied being connected to the Bangladeshi government, despite evidence showing members of the Awami League’s UK arm campaigning for her in previous elections.

Kiran Stacey

David Bergman

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