The Chief Constable of Sussex could quit within months to take up a new job.

Ken Jones is favourite in the ballot for a new president of the Association of Chief Police Officers (ACPO) and if successful would start his new job next May.

Mr Jones, credited with turning round the fortunes of what was a failing police force, confirmed he had applied for the post.

The only other candidate is Terrance Grange, chief constable of Dyfed-Powys, but Mr Jones is seen as the clear front runner.

It is the second time in a year Mr Jones has signalled his intention to leave the force.

Mr Jones was beaten to the £225,000-a-year job of Metropolitan Police Commissioner last autumn by Sir Ian Blair.

The 200 ACPO members, all senior police officers, are voting now on the presidency and the closing date is September 7.

The chief constable, currently earning £115,000, would negotiate his salary as ACPO president but it is thought he would earn in the region of £170,000.

He would take over from Chris Fox who is coming to the end of his three-year tenure.

Mr Jones, ACPO's terrorism spokesman, said if he got the job he would be leaving Sussex eight months earlier than expected.

He said: "I have a five-year contract with Sussex and that ends in November next year."

If Mr Jones is unsuccessful in his ACPO application he could find himself out of work.

Chief constables have traditionally served beyond their five-year contracts but requests for extensions are now being turned down by police authorities and the Home Secretary.

Only one chief constable out of 15 who applied in recent years was successful.

When Mr Jones applied for the commissioner's position last year he said being Chief Constable of Sussex was the only other position he wanted to hold.

Yesterday, he said, he went for the ACPO job after being persuaded by colleagues - "There was a lot of pressure for me to stand and a lot of viable candidates stood aside for me to do so."

Mr Jones said it was perhaps time for a new Sussex chief to "push things in another direction" but he would be sorry to leave.

Mr Jones, 53, said after losing out to Sir Ian Blair: "I have one of the best jobs in the country. Things are going well at the moment.

"After a lot of hard work two or three years ago, things are now beginning to pay off." He has been chief constable since 2001 and took over after Paul Whitehouse was forced to resign in the wake of the fatal shooting of James Ashley in Hastings.

Under Mr Jones' leadership, Sussex Police has climbed the national performance league table. It was once firmly bottom and is now mid-table.

Mr Jones scrapped the idea that police forces could be "smaller, better, different" and reintroduced more traditional policing methods including neighbourhood policing.

The hiring of more police and community support officers meant greater visibility and more bobbies on the beat, something the public had demanded.

If Mr Jones fails to secure the ACPO job, he said he would not be sorry to remain with Sussex Police.