A New Zealand woman has been jailed in the UK after she was found to have provided fake qualifications to work as a doctor for more than two decades.

Zholia Alemi was last month jailed for five years after eventually being found out when she was convicted of trying to fake the will of an elderly female patient.

Had she been successful, she would have stolen up to £1.3 million (NZ$2.4m) of the woman's fortune.

A judge described her as "despicable" and jailed her for five years last month.

The New Zealander's two-decade deception has sparked urgent checks in Britain - with 3000 foreign doctors to have their credentials investigated.

Alemi, 56, claimed to have a degree from the University of Auckland in New Zealand when she came to work in the UK in 1992.

In reality, the convicted fraudster had flunked her first year and dropped out.

But nobody at the General Medical Council, the watchdog responsible for vetting the background of medics, checked whether her documentation was genuine.

Alemi, 56, is said to have provided a Bachelor of Medicine and a Bachelor of Surgery certificate from the University of Auckland when she arrived in the UK in the early 1990s.

At that time, doctors from certain Commonwealth countries could be cleared to start work simply by presenting their qualifications, without sitting any assessments.

Alemi held a degree in human biology.

For the next 22 years, starting in 1995, she worked as a psychiatrist for the UK's National Health Service - treating thousands of mental health patients over that period and potentially earning up to £100,000 ($188,000) a year.

She also reportedly drove a Lotus Elise sports car.

'Despicable' attempt to steal elderly woman's fortune

A judge described her as "despicable'' when she was sentenced last month, according to the Daily Mail.

Alemi was last month found guilty of four fraud and theft charges after a week-long trial at Carlisle Crown Court.

The New Zealander met Gillian Belham, now aged 87, at a dementia clinic in Workington in February 2016.

Within four months she had redrafted Belham's will - and fraudulently applied for power of attorney.

Belham's extended family and a raft of charities were "entirely written out" of the bogus will.

Instead, Belham's assets were to be held in a trust for the benefit of Alemi's grandchildren.

Judge James Adkin said Alemi's offending was "wicked.''

"This was despicable, cruel criminality motivated by pure greed and you must be severely punished for it."

Alemi had received warning over careless driving

Patients' groups called for a public inquiry as police confirmed their investigation into Alemi was ongoing.

John Woodcock, independent MP for Barrow and Furness, in the Lake District - where Alemi was most recently working - said the case was "hugely alarming."

"If this had been one individual that had slipped through the net it would have been concerning, but the idea that it could be a systemic loophole that has been exploited is hugely alarming," he said.

"It is understandable that patients are calling for an inquiry – this is of sufficient magnitude that that may well be necessary."

The General Medical Council admitted its checks had been inadequate and confirmed an 'urgent investigation' was looking into the backgrounds of 3000 doctors who came to work from Commonwealth countries, before 2003, in the same way.

Incredibly, Alemi had been investigated and given an official warning by the Medical Practitioners Tribunal Service in 2012 after failing to disclose a conviction for careless driving.