A nurse who set himself on fire outside Kensington Palace was kept waiting 93 days for a disciplinary hearing, an inquest has heard.

Amin Abdullah, 41, died on February 9 last year close to the London home of the Duke and Duchess of Cambridge, after losing his job at Charing Cross Hospital where he worked as a charge nurse.

The inquest into his death heard that he had written a letter for another colleague caught up in a complaint made by a patient to "show how she could respond" - resulting in him becoming embroiled in the issue.

His partner, Terry Skitmore, giving evidence on Monday, said Mr Abdullah slipped into a depressive state during a disciplinary investigation which began in September 2015 and after he subsequently lost his job at Imperial College Healthcare NHS Trust.

Lesley Powls, head of nursing at the trust, said in her evidence at Westminster Coroner's Court on Wednesday that they have "apologised publicly and privately about the delays in his disciplinary case".

The inquest heard that from September 15 until his disciplinary hearing meeting on December 16, Mr Abdullah was kept waiting and was "unaware of the outcome" - a period of 93 days.

Ms Powls said the delays were due to a number of reasons.

These included the workload of the investigating senior nurse, as well as this staff member also being involved in the roll-out of a new electronic system, on top of a shortage of staff.

Ms Powls said these were "not excuses" and revealed the average length of time for the disciplinary process has fallen from 72 days as of March last year, to 64 days since.

When questioned by Coroner Dr Shirley Radcliffe on whether the delays were of some significance in the mental health and state of Mr Abdullah, Ms Powls said it was "difficult" for her to determine because she is not a psychiatrist.

But she added: "A lengthy and protracted period where someone is unsure about the outcome ... would be distressing."

The written case against Mr Abdullah was completed by October 22. The investigation into his colleague was then carried out and concluded on November 17.

Both their disciplinary hearings were held on the same day.

The inquest heard that Mr Abdullah had addressed his mental health with his GP, who had signed him off sick - but that he had chosen to remain at work.

Caroline Cross, representing Mr Skitmore, also highlighted how different emails were sent to "at least three" staff at the trust, indicating Mr Abdullah's mental health issues.

She said one of these included a Royal College of Nursing representative who contacted the trust over the "unreasonable delay" in Mr Abdullah's case.

The email sent on December 10 highlighted his "anxiety and stress" and stated that this was affecting his mental and physical health.

On December 21 2015 Mr Abdullah was handed an instant dismissal on the grounds that the letter he had written to support his colleague was "untrue".

The inquest has previously heard that on January 27 last year Mr Abdullah was voluntarily admitted to St Charles Mental Health Unit after he had tried to commit suicide.

Malaysian-born Mr Abdullah had lodged an appeal against his dismissal in January 2016 and a hearing date had been set for February 11.

Just days earlier, he was allowed out of the unit to collect a suit for the meeting but never returned as agreed. He was later discovered alight and died on February 9.

The inquest continues, with the coroner expected to deliver the verdict later on Wednesday afternoon.