Mid Suffolk: Green council win not a protest vote - leader
The leader of the first council to be won outright by the Greens said votes for his party could no longer be considered as purely a protest against the other main parties.
They won 24 of 34 seats on Mid Suffolk District Council, six more than was needed for majority.
It was previously run by a 16-seat minority Conservative administration.
"We are a serious political party," said Andy Mellen, leader of the Green Party in Mid Suffolk.
"We got 57% of the vote in Mid Suffolk, we gained seats right across the region.
"I don't think we can call it a protest vote any more. We are a serious political party and we are winning seats and doing very well."
After looking at the financial position of Mid Suffolk, Mr Mellen said he was confident the party could create change without raising council taxes for residents.
Victory in Mid Suffolk is the first time the Greens have had a majority on a council anywhere in England, although they have been involved in ruling as minority administrations or as part of coalitions at other councils, including Brighton, where Caroline Lucas is the party's only MP at Westminster.
Mr Mellen told the BBC's Politics East programme: "The size of the victory did surprise us a little bit [although] we thought we would get a majority; we saw that coming quite a long way out.
"And it's a really positive vote for the Greens in Mid Suffolk and across the region; we did exceed expectations there's no doubt about it, 24 seats out of 34 was bigger than our wildest dreams."
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