Bristol mayor concerned underground will not go ahead
The Bristol mayor said he "does not know" whether his plans for a Bristol underground will be carried out after he leaves office next year.
Marvin Rees told BBC Radio Bristol: "People are getting tied up in the description that it sounds too fanciful, but we need a transport solution for Bristol."
Earlier, a report showed an underground rail network could cost up to £18bn.
Marvin Rees had previously estimated the cost at £4bn.
He said the £18billion figure was based on the entire project going underground, which was "not necessary" in many areas.
Mr Rees added Bristol's current population of 472,000 would grow to 550,000 by the middle of this century, and that during the day there were about a million people in the city.
"So whichever way we cut it up we need a transport system that transports masses of people around the city each day," he said.
Marvin Rees' term ends in May 2024.
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