Boris Johnson's top aide, Dominic Cummings, has defended his controversial journey to County Durham and stated he behaved "reasonably" and does not regret his actions.

In a highly unusual press conference in the rose garden of 10 Downing Street, the Prime Minister's chief adviser said he made the journey because of fears over a lack of childcare if he became incapacitated with Covid-19, but also concerns about his family's safety.

Mr Cummings said stories suggested he had opposed lockdown and "did not care about many deaths", but he told reporters: "The truth is that I had argued for lockdown.

"I did not oppose it, but these stories had created a very bad atmosphere around my home, I was subjected to threats of violence, people came to my house shouting threats, there were posts on social media encouraging attacks."

Mr Cummings said he was worried that "this situation would get worse", and "I was worried about the possibility of leaving my wife and child at home all day and often into the night while I worked in Number 10".

"I thought the best thing to do in all the circumstances was to drive to an isolated cottage on my father's farm," he added.

He said he was told at around midnight on March 26 by the Prime Minister that he had tested positive for Covid-19.

After discussing the national emergency arrangements, Mr Cummings said he went to Number 10 the following day for a series of meetings.

He received a call from his wife, who was looking after their four-year-old child, who said she felt badly ill, had vomited and felt like she might pass out.

That led to Mr Cummings' decision to swiftly leave No 10 - actions that were caught on camera in Downing Street.

After a couple of hours his wife felt better and Mr Cummings returned to Downing Street.

But he said that evening he discussed the situation with his wife - including the fact that many in Number 10 had developed coronavirus symptoms.

He was worried that if both he and his wife fell ill there was "nobody in London we could reasonably ask to look after our child and expose themselves to Covid".

Mr Cummings said that he drove up to Durham with his wife and son and did not stop on the way.

He said the next day he woke up in pain and "clearly had Covid symptoms".

He added: "So I drove the three of us up to Durham that night, arriving roughly midnight. I did not stop on the way.

"When I awoke the next morning, Saturday March 28, I was in pain and clearly had Covid symptoms including a headache and a serious fever.

"Clearly I could not return to work anytime soon. For a day or two we were both ill, I was in bed, my wife was ill but not ill enough to require emergency help."

Mr Cummings said that on April 2 his son fell unwell and was taken to hospital but he was still too ill to go with him.

He added: "During the night of Thursday April 2 my child woke up, he threw up and had a bad fever. He was very distressed.

"We took medical advice which was to call 999, an ambulance was sent, they assessed my child and said he should go to hospital.

"I could barely stand up, my wife went with him in the ambulance, I stayed at home, he stayed the night in hospital."

He said that in the morning his wife called to say their son had recovered and could return home.

Mr Cummings said that he drove to the hospital to pick up his wife and son but did not leave the car or come into contact with anyone on the way.

He said as he was recovering he went for a walk in the woods next to the cottage they were staying at which was private land and while they saw some people they had no interaction with anyone.

Mr Cummings said that by April 11 he was still feeling "weak and exhausted" but had no Covid symptoms so thought he would be able to return to work the following week - possibly part-time.

He added: "It was obvious that the situation was extremely serious, the Prime Minister had been gravely ill, colleagues were dealing with huge problems and many were ill or isolating.

"I felt that I should be able to return to work if possible given I was now recovering in order to relieve the intense strain at Number 10."

Asked about the nature of any contact with his parents, Mr Cummings said he had had "shouted conversations" with them from a distance.

He said: "I was in a cottage, 50 metres or so away from everybody else. Obviously we kept very, very far away from them. There are various reports that I visited them, I was staying with them. That's all completely untrue.

"My parents are in their 70s. Obviously I did not want to give them this disease. And so we stayed very far away.

"We did have some conversations but they were on a farm and they were shouted conversations at a distance. They weren't some of the things that have been reported."

The defence of his actions comes amid furious calls for him to resign or be sacked by Mr Johnson for travelling to County Durham in March to self-isolate with his family after his wife developed coronavirus symptoms.

Mr Cummings denied further reports which suggested he took a second trip to the North East on April 14.