Jones has presented programmes including Restoration and Rivers with Griff Rhys Jones
Comedian Griff Rhys Jones has hit out at TV bosses for making commissioning decisions based solely on ratings.
Jones, 56, said no-one trusted him to present a TV series until they had the ratings figures for the last series.
He said he did not know whether another series of ITV1's Greatest Cities with Griff Rhys Jones would be commissioned.
He also blamed the ratings game for keeping comedy sketch show Alas Smith and Jones going for too long. It ran on the BBC from 1984 to 1998.
"Trying to write 13 series of sketch shows is just an exhausting mountain to climb and we did it for that long because every time I said 'I've had enough', they'd say 'Oh, but the ratings are good, do another one'.
"So you go on until one day they say: 'The ratings aren't very good, get off," Jones said.
He said it was not his decision to stop doing TV comedy.
"I did spend a little bit of time knocking on doors and realising that they weren't going to do what I wanted to do," he said.
He said the fickle world of television has left him enjoying the work he is doing at the moment.
"It's all a whim, people change, people at the top change so the one thing you need to do is do it while it's there because at one point someone's going to arrive and say: "Not him, I don't want him anymore.'"
The new series of Greatest Cities with Griff Ryhs Jones starts later this month on ITV1.