Professor Stephen Hawking says he would consider assisted suicide if he felt he had become a burden to his loved ones.

The award-winning theoretical physicist, who is paralysed as a result of motor neurone disease, is an ardent supporter of a person’s right to die.

Professor Hawking, 73, admitted he would consider taking the step himself if he was in great pain.

Professor Hawking, who suffers from a rare form of motor neurone disease, said he would consider assisted suicide if he were in 'great pain' or had become 'a burden to those around me'

He said refusing terminally ill people the right to die was 'the ultimate indignity'.

In an interview with comedian Dara O’Briain, he said: ‘I would consider assisted suicide only if I were in great pain or felt I had nothing to contribute, but was just a burden to those around me.’

However, the Cambridge scientist insisted he had no plans to slow down yet, adding: ‘I am damned if I’m going to die before I have unravelled more of the universe.’

Prof Hawking suffers from a rare, slow-progressing form of motor neurone disease that has gradually paralysed him over the decades.

Prof Hawking said he missed not being able to play physically with his children when they were young. Here he is pictured with his children Robert and Lucy in the 1970s

He told O’Briain, who has a degree in maths and theoretical physics, that his condition sometimes left him feeling isolated, The Daily Telegraph reported.

He said: ‘At times I get very lonely because people are afraid to talk to me or don’t wait for me to write a response.

‘I’m shy and tired at times. I find it difficult to talk to people I don’t know.’

The scientist also opened up about the difficulties of being a father with the condition.

He said: ' I would like to be able to swim again. When my children were young, I missed not being able to play with them physically. '

The interview, to be broadcast on BBC1 on June 15, will also show Prof Hawking’s daughter Lucy, 45, and son Tim, 36, discussing their father’s life and work, alongside several of his Cambridge students.

In a 2013 interview, the physicist stressed that while he supported assisted dying, he believed safeguards should be in place to prevent abuse.

He said: 'There must be safeguards that the person concerned genuinely wants to end their life and they are not being pressurised into it or have it done without their knowledge or consent, as would have been the case with me.'

Prof Hawking was given only two years to live after being diagnosed with motor neurone disease just after his 21st birthday.

Experts say only 5 per cent of people with his form of MND – a condition called amyotrophic lateral sclerosis or Lou Gehrig’s Disease – survive for more than a decade after diagnosis.

Almost 300 Britons have travelled to Swiss assisted suicide clinic Dignitas to end their lives.

Britons made up the second highest number of foreigners going to Zurich for assisted suicide between 1998 and 2014, exceeded only by Germans.

The organisation said 273 Britons had killed themselves with its help in its first 16 years, compared to 920 Germans and 194 French.

Dignitas was founded in 1998 to help people with terminal and incurable illnesses to kill themselves in Switzerland, where assisted suicide is permitted in specific circumstances.

'Patients' must prove they are of sound judgment and be able to administer a lethal dose of a drug themselves.

In 2010 the organisation's fees were said to be almost £3,200 for preparations and the assisted suicide, rising to more than £6,500 for those wanting funerals, medical costs and other fees covered.