Speaking to the Sun on Sunday Chris, 67, said he thought he was going to die when he realised he couldn't move his arms and legs properly during an 11-hour flight from Bangkok to London on 1 March.
"I was trying to stretch to make it go away," said Chris who also felt a pain in his hand and fell off his seat unexpectedly. "I became more and more frightened - then the realisation hit that it was a stroke."
Calling it the "most terrifying moment of my life" Chris is said to have refused to tell the plane's cabin crew about his illness for fear they would tell him there was nothing they could do to help.
"I got very panicky," he said. "I was very alone up there, thinking, 'I could die'. I wasn't sure if I was going to fade away completely on my own."
With that thought in mind, Chris tried to call his long-term girlfriend Jane Bird who has been his partner for seven years.
"I am incredibly lucky to be alive because one in three people who have strokes don't make it," he said. "It has made me appreciate my life so much more."
Chris and his partner Jane Bird
According to the Daily Mail the former Who Wants To Be A Millionaire? presenter managed to drag himself through passport control before collapsing, at which point a 'mystery couple' called him an ambulance.
After paramedics arrived on the scene the father-of-four was taken from Heathrow to Charing Cross Hospital in central London where doctors discovered that the cause of the stroke was a blood clot in his leg.
Keen to thank the British couple who came to his rescue, Chris said he hopes to find out who they are adding, "What they did for me was amazing."
Chris quit hosting Who Wants To Be A Millionaire in February
Chris told the Sun that two months on he still has not regained full control of his movements or speech but has been undergoing physiotherapy and has made changes to his lifestyle to minimise the risk of suffering another stroke.
"I've done a lot to excess," he said, in reference to drinking, smoking and working long hours. "[Now I'm] on the straight and narrow."
Chris had been returning to the UK after filming a new travel series in Burma, which is due to air later this year, although he has said that at the moment he has no plans to get back to work and is recuperating at his home in Bucklebury, Berkshire.