He said while he and other people he had spoken to thought there were MPs in the party who could become good leaders in the future, he thought it was not a good time for a potential change.
"I think anyone else who'd try to take over the job would be in a worse situation trying to convince the Labour Government, and a new leader wouldn't be in the Climate Change portfolio, James will keep that portfolio anyway."
After the vote, Shaw spoke to Prime Minister Jacinda Ardern, who confirmed that he would retain his role as climate change minister whether he regained his role as co-leader of the party or not.
Milnes, who's also the chairman of Sustainable Whanganui, said he supported Shaw regaining his position in the party, as he was doing as good of a job as he possibly could.
"A lot of the opinion within the party is that he is a bit more business-minded but I think it's totally tempered by his opinions on climate change," he said.
Since the vote to oust him, Shaw has confirmed he will run to regain his position, with no other MPs having confirmed they would run against him as yet.
Milnes expected Shaw would retain his position of co-leader believing he had enough support from within the party.
"I think he'll get back without any trouble.
"I think there are enough members who believe that he's doing a good job and I think it's not a good time to be chasing up a new co-leader," he said.
