McFadden insists he has full confidence in under-pressure minister Siddiq

Chancellor of the Duchy of Lancaster Pat McFadden said Tulip Siddiq had 'done the right thing' by asking the ethics tsar to investigate her.​

Under-fire Treasury minister Tulip Siddiq has been backed by one of Sir Keir Starmer's most senior allies after she referred herself to the Prime Minister's ethics tsar.

The independent adviser on ministerial interests, Sir Laurie Magnus, is looking into Ms Siddiq – who has anti-corruption responsibilities in her role as Treasury economic secretary – over allegations about properties linked to her aunt's political movement in Bangladesh.

Chancellor of the Duchy of Lancaster Pat McFadden said he had full confidence in Ms Siddiq and she had acted properly by referring herself to Sir Laurie. Tulip Siddiq's aunt is the former Bangladesh prime minister Sheikh Hasina, who fled into exile after being deposed last year. The former prime minister is facing an investigation by an anti-corruption commission in Bangladesh, with Ms Siddiq reportedly named as part of the case.

The minister was alleged to have been involved in brokering a 2013 deal with Russia for a nuclear power plant in Bangladesh in which large sums of cash are said to have been embezzled. She has also come under intense scrutiny over her use of properties in London linked to her aunt's allies.

She was reportedly given an apartment in King's Cross in 2004 by Abdul Motalif, an associate of members of the Awami League party in Bangladesh. She had also reportedly lived in a flat in Hampstead, north London, which had been given to her sister by lawyer Moin Ghani, who had represented the Hasina administration.

McFadden, whose influence in government has led to him being dubbed the "real deputy prime minister", was asked by Times Radio if he had full confidence in Siddiq.

McFadden replied: "Yes." He added: "She has done the right thing. All these allegations have been made, and she has referred all of them to the independent adviser on ministerial interests. "When we won the election six months ago, we boosted the powers of the independent adviser in the new ministerial code that was issued, to make sure that he had the power to initiate and carry out investigations into allegations like this. "That is what he is doing, and that is the right way to deal with this."

Tulip Siddiq pulled out of Rachel Reeves' trip to China in order to deal with the allegations against her. In her letter referring herself to Sir Laurie, she said she was "clear that I have done nothing wrong".

The Conservatives have called for Siddiq to be sacked, while Bangladeshi leader Muhammad Yunus said London properties used by Ms Siddiq should be investigated and back to his government if they were acquired through "plain robbery".

He also called on her to apologise and resign, telling the Sunday Times: "She becomes the minister for anti-corruption and defends herself. "Maybe you didn't realise it, but now you realise it."