Webber, who arrived from Huddersfield in April, is heading up the search for a permanent replacement for Alex Neil.
"We have a list of candidates, and once their seasons are finished, we can start to accelerate that process," Webber told BBC Radio Norfolk.
Northern Ireland boss Michael O'Neill has distanced himself from the role.
Neil was sacked by the Canaries on 10 March, with Alan Irvine taking the team on an interim basis for the rest of the season.
Webber said he still expected the new head coach to be in place by the end of May.
"We have a clear idea of the type of person it'll be," he added.
"Things are a little bit slow because people's seasons are still going on and we have to be respectful of that.
"There's certain rules that we have to adhere by."
Webber also reaffirmed Norwich's interest in signing Ajax left-back Mitchell Dijks, 24, on a permanent deal, following a successful loan spell, while playing down speculation over Steven Naismith's future at Carrow Road.
"With Mitchell, we have the option to buy him, so to a certain degree it's our call," he said.
"We need to agree personal terms and from a financial point of view we need to be creative with the squad, so if that means Mitchell or any other player we're trying to get falls out of that, we can't do it.
"I had a laugh with Steven the other day about what came out of the media in Scotland, saying he was going to be let go on a free.
"It's news to me, and it's news to Steven. He's a good player, we all know that, [with] unbelievable experience at the highest level, in terms of international football.
"He's our player, he's under contract."
Norwich City's next head coach will come from a shortlist of managers currently in jobs, sporting director Stuart Webber has said.