Tim Hollis was appointed chief constable in April 2005
The head of Humberside Police is to take temporary charge of the organisation which guides police forces across the UK.
Chief Constable Tim Hollis will be based in London to lead the Association of Chief Police Officers (ACPO).
He is filling in for Northern Ireland's Chief Constable Sir Hugh Orde, who will become ACPO's new president in August.
Humberside's Deputy Chief Constable Dave Griffin will lead the force during Mr Hollis's absence.
Mr Hollis was appointed one of the three vice presidents of ACPO last year.
He said: "There's a good deal happening in respect of policing just now and we considered it important to have someone overseeing the business until his arrival.
"I'm grateful to my police authority for supporting the temporary arrangements and it's good to feel that Humberside is able to provide support to policing at a national level.
"I know Hugh Orde well and I'm much looking forward to working with him to meet the policing challenges that confront us."
In a statement, Humberside Police Authority said: "This shows the high regard in which our chief constable is held by his peers and we wish him well."