The organisation representing rank-and-file police officers in Scotland has warned it will "escalate" action in its pay dispute if it does not receive a better offer.

The Scottish Police Federation unanimously rejected a 3.4% pay rise proposal on Wednesday after it said the deal "continues to fail to recognise the unique role of the police offer and is significantly lower than offered in other sectors".

And, the organisation warned: "Unless a further improved offer is received by Friday August 5 that the actions of our members in response to this continued dispute will escalate."

Police officers cannot strike, but the 17,500 members of the SPF withdrew "all goodwill" after a "derisory and insulting" pay offer of £565 which "must have been known to be so prior to being presented".

It has meant since the start of this month rank-and-file officers have, among other things, refused to start shifts early or take radio equipment home when their shift ends.

The warning from the federation on Wednesday could mean next month officers go further in these actions.

A federation spokesman said: "Police officers should not be in a position where Government values police offers less than other sectors and workers.

"The unique role of the police officer should always be reflected in any pay offer. This revised offer, like it's predecessor, fails to do so."

Police pay is negotiated through the Police Negotiating Board, which includes police officer staff associations, the Scottish Police Authority, Police Scotland, and the Scottish Government.

In the latest deal rejected by the federation, all pay points for all ranks would see their salaries rise by 3.4%, backdated to April 1.

Allowances would also rise by the same amount, the official side of the Police Negotiating Board said, and added in their letter to the staff side negotiators: "Since the original offer made in May was rejected by the staff side, our focus has remained on trying to reach an agreement within the PNB.

"Consequently, significant efforts have been made to explore ways we might be able to make an improved and affordable offer that appropriately recognises the important and valuable contribution police officers play within society.

"This has been challenging in the current financial context but we understood the need to do more if we were to reach an agreement on pay and conditions for 2022."

On Tuesday, officers south of the border were offered a 5% pay rise after the Home Office said it accepted recommendations from the independent police pay review body in full.

Calum Steele, general secretary for the Scottish Police Federation, said the pay deal agreed by Home Secretary Priti Patel was "highly significant" in the ongoing dispute.

He said it was "notable that at every stage of their pay process, all key employer representatives, from the Home Office itself, through to chief constables, advocated for a higher award than the initial starting position of the Scottish official side of the Police Negotiating Board".

A Police Scotland spokesman said: "We are monitoring the situation in relation to the withdrawal of goodwill. We will put arrangements in place to ensure any impact on the public is kept to an absolute minimum.

"We recognise the considerable goodwill officers bring to their roles on a daily basis as they keep people safe across the country, and this is also valued by the communities they serve.

"We therefore remain committed, through the Police Negotiating Board, to seeking a settlement."