They've both been vocal in their concern with dealings over Shelly Bay.
But developer Ian Cassels has made a point of reminding Foster he is no longer a councillor.
"He has a different role, he bears responsibility more so than ever in the past. The mayor is the cheerleader and is responsible for progress, whereas a councillor has the luxury to criticise, stop, and do all sorts of things."
"In his current role he needs to lead the city, you can't lead the city with no, you can't lead the city with crossing t's and dotting i's, and not having houses."
The next step in the saga is for city councillors to again vote on whether to lease and sell council land at Shelly Bay, because so much has changed since the first 2017 vote in favour.
Cassels said he was willing to iron out any issues councillors had, but thought they'd vote in favour once they understood the infrastructure cost ratepayers would otherwise be lugged with.
He said a deal was a deal and if this latest vote swung in the opposite direction to the first one, the council could open itself up to litigation.
"I wouldn't want to contemplate a city that couldn't keep its word."
Foster told the Herald he had not yet read the decision, but said that on the face of it the result did not surprise him.
"I would have been delighted had the outcome been slightly different, but I'm not surprised.
"This is the inevitable result of a poor piece of legislation that prevents the community from having a say."
Outgoing mayor Justin Lester said the decision would be difficult for Foster.
"As a political or elected representative it's really important that you respect judicial process, that you take cognisance of the reasons that have been given and the legislation that's in place."
Wellington City Council chief executive Kevin Lavery issued a note with the resource consent decision.
He said consent conditions were overall consistent with those imposed when council officers granted the original consent.
"Please also note that we will be coming back to Council with a general update on the decision, including a final decision on the sale and lease of Council land and upgrade of roading infrastructure, in due course", Lavery said.