Kweku Adoboli, the former UBS banker jailed for the UK’s biggest ever fraud, will on Monday file for a judicial review of the decision to deport him to Ghana, in a last-ditch attempt to stop his “banishment” from the UK, where he has lived since he was 12.

Adoboli, 38, who was found guilty in 2012 of fraud that lost his Swiss bank $2.3bn (£1.8bn), is being deported to Ghana because he is not a British citizen, despite having lived in the UK for 26 years.

Adoboli, who is being held in an immigration removal centre near Heathrow airport, is expected to be placed on a flight to Accra, the Ghanaian capital, on Tuesday.

Under UK law, if a foreign national has been sentenced to more than four years in jail “the public interest requires deportation unless there are very compelling circumstances”. Adoboli was sentenced to seven years and served half of that time.

The supreme court suggests the compelling circumstances to consider for the prevention of deportation are close relationships with children and long-term partners, and long-term employment. Adoboli does not have children, is in a newly formed relationship and is prevented from carrying out paid work by the terms of his release.

His lawyer, Jacqueline McKenzie, said the judicial review would seek to highlight the charitable work Adoboli has been doing to educate others in the financial services industry and wider community to learn from his mistakes. His work has included training courses for the Ministry of Defence, the Ministry of Justice, the Home Office and Barclays. On one three-day officer development course for the UK special forces he and Tony Blair were the keynote speakers.

Adoboli is also appealing to the prime minister and the home secretary to “show some compassion” and intervene to prevent his “banishment”. Some 114 MPs and MSPs have signed a letter to Theresa May and Sajid Javid demanding they intervene to stop Adoboli’s deportation.

“If Mr Adoboli were deported, he will be removed from the country he has called home since the age of 12, taken away from the close relationships he has formed here and returned to a country he has not lived in from the age of four and lacks familiarity with,” his MP, Hannah Bardell, said in the open letter.

She added: “The recent comment by the former home secretary Amber Rudd MP that ‘the Home Office has become too concerned with policy and strategy and sometimes loses sight of the individual’ is apt in this case and we are sure no one in the cabinet wishes to have another ‘Windrush Generation’ scandal on their hands anytime soon.”

More than 73,000 people have signed a petition supporting the campaign to keep Adoboli in the UK.

Adoboli, who was earning £350,000 a year in his 30s, said: “I did four years in prison for a nonviolent act. I’ve served my time but I’m being given an extra punishment – a banishment – and just because I didn’t get around to becoming a citizen. This punishment is so much worse than being in prison.

“Prison is a finite; you do your time, you hold your head high and you know you will get out. This [being deported] is really inhumane.”

Adoboli believes there are racist overtones to his treatment. “People say it is OK for me to be sent back because it is where I am from,” he said. “But I left when I was four. My life is here, my friends are here. If I were British my punishment would be over and I could get on with life.”

Not becoming a British citizen when he had the opportunity was, he said, the biggest oversight of his life. “Ironically, it was because I was trying to be good at my job that I didn’t go through the citizenship steps,” he said. “I was the public face of UBS’s Delta One desk running a £50bn portfolio. At the drop of a hat I had to get on a plane to Frankfurt, New York or the Eurostar to Paris. I kept my passport in my desk drawer.”