12 directly elected mayors planned for big cities

The Financial Times reports that the Government are planning to press ahead with plans for directly elected mayors in 12 big cities. It suggests Birmingham, Bristol, Newcastle, Liverpool, Manchester, Leeds and Sheffield would be included. 

The FT gets suspicious about the reference to "confirmatory referendums." They think they might make the existing Council leader the mayor first and then have a referendum to confirm the arrangements. I would be surprised if this interpretation was accurate. Such people would not be directly elected mayors. If they were incumbent before the election that would seem unfair.

Also the coalition agreement said:

We will create directly elected mayors in the 12 largest English cities, subject to confirmatory referendums and full scrutiny by elected councillors.

So this word "confirmatory" has not just been suddenly added. I interpret it to mean the posts will only be created once the referendum has granted approval.

On the other hand I suppose a referendum after an event has taken place is easier to win. My mother says she would have voted against Britain joining the Common Market had their been a referendum in 1972, before we went in. But that in 1975 she voted Yes because she felt pulling out again would be disruptive.

Who will get these referendums? Apart from those mentioned by the FT the others in the list of the largest 12 English cities, by population, are Bradford, Wakefield, Coventry, Nottingham and Leicester. Sunderland doesn't make the cut.