Richard Hammond has hinted Jeremy Clarkson could be close to retiring.
The 'Grand Tour' co-host has sparked speculation his 58-year-old fellow TV presenter - who he worked with on 'Top Gear' from 2002 to 2015 - could be "put out to pasture" in the near future.
He said: "I think he is getting on and at some point we should him put him out to pasture, maybe in a lake."
But Richard, 48, has heaped praise on Jeremy for his latest role as host of the revamped 'Who Wants to be a Millionaire?', and joked the job is "ideal" for him because he can do it sitting down.
He added: "I think is a natural born quiz show host.
"It is a job he can do sitting down, which at his age is ideal.
"Annoyingly I think he is very good, largely because it is indoors."
Richard remained coy on whether 'The Grand Tour' - which the pair present alongside James May - would return for another run.
He is quoted by the Daily Star newspaper as saying: "It is all top secret."
This comes after speculation emerged that the show may not return after Jeremy was asked to present 'Millionaire'.
A source recently said: "There is nothing to suggest they are going to do another [series of 'The Grand Tour'].
"No one has signed anything and employees are wondering where everyone will go once filming wraps."
But the show's producer Andy Wilman refused to comment on whether there will be a series four.
He said: "We are focusing on series three at the moment."