Mr Herbert spoke to the SDNPA board last Thursday.
He said the bypass would give environmental benefits to the National Park by taking away traffic that currently ‘rat-runs’ through the South Downs
However following a brief discussion SDNPA board members voted by a substantial majority to reject all three routes.
Mr Herbert said: “I hope that, as discussions continue and when Highways England consult on their preferred route next year, the authority will take a more evidence-led and balanced view.
“They do not have a veto on the bypass and simply rejecting it means they are supporting the option that is most damaging to the South Downs.”
The first A27 consultation closed on October 16.