Leaders of 18 Yorkshire councils have written to Theresa May urging her to commit to a region-wide mayoral election in 2020, ahead of a crunch meeting with the Communities Secretary tomorrow.
Sajd Javid agreed to tomorrow's meeting, where he will hear from council leaders on their plans for a regional devolution, last month.
Members of the All Party Parliamentary Yorkshire and North Lincolnshire Group, including all of the region's council leaders, MPs, peers and invited businesses, trade unions and religious leaders, will meet at the Commons at 4pm on Tuesday - in a meeting that has been previously described as "very significant" for Yorkshire devolution by Keighley MP John Grogan.
Ahead of the meeting, a letter signed by the 18 leaders - including Coun Peter Box from Wakefield, Coun Judith Blake from Leeds, Coun Carl Les from North Yorkshire, and leaders of York, Barnsley and Doncaster councils, tells the Prime Minister that they have "now reached agreement" on devolution.
It says the group believe South Yorkshire should benefit from its devolution deal first, with a two-year mayoral term beginning after the planned election in May, and that a "joint commitment" should be made now between the Government and local authorities in Yorkshire for a Mayoral election in May 2020 "involving any councils who decide to join a Mayoral Combined Authority for the widest possible Yorkshire geography".
The letter states: "We believe that there are many benefits to be gained from this approach by Government and the people and businesses of Yorkshire and therefore negotiations about the deal should start without delay."
It says that with the Government's support, tomorrow's meeting "can seal an historic agreement about devotion to benefit all of Yorkshire's £5m people by potentially doubling the size of our economy."
The letter was also signed by leaders from Bradford, Calderdale, East Riding, Hull, Kirklees, York, Craven, Hambleton, Richmondshire, Scarborough, Selby, Ryedale and Harrogate.
See Tuesday's The Yorkshire Post for more.