Ross (Lib Dem) and Handley (Conservative), who are lead members on its executive board, said in their letter to the minister: “We recognise that the process of establishing the combined authority is not a quick or easy one… both in terms of putting together the officer resources and setting out the direction of the region under the mayor’s vision.
“In recent months there has been increasing cause for concern with the direction and leadership of the authority.
“Recruitment to key roles has been problematic and there is little clear evidence of a vision for the region under the organisation.”
The letter also points to concerns recently voiced by Humberside’s Police and Crime Commissioner, Jonathan Evison, and his deputy, Leo Hammond, who have written to the prime minister, stating a “lack of action and vision” at the mayoral authority.
In a statement, Campbell said: “Both Anne and Mike wanted to be mayor. They stood against me, the public had their say and they made their choice.
“I’ve got absolutely no problem with being challenged or held to account, but there’s a difference between proper scrutiny and political point-scoring.
“They’re not spectators. They’re part of its leadership. Anne has the investment portfolio, Mike has skills, and both sit around the board table making decisions alongside me.
“So when they question the direction of the organisation or what’s been achieved, I think it’s only fair to ask what they’ve contributed in their own areas.”