The result of a historic vote by police officers on whether to seek the right to take industrial action are set to be revealed.
The outcome could set the coalition Government on a collision course with rank and file policemen and women across England and Wales following rows over spending cuts.
Federation officials said 20% cuts to policing, combined with "attacks" on pensions, pay and conditions, have resulted in a period of "unprecedented discontent and low morale" among police officers.
Relations worsened after a report by former rail regulator Tom Winsor recommended that police forces should face changes to pay, conditions and recruitment.
Suggested reforms included cutting pay for new police constables by £4,000 to £19,000, as well as a fast-track scheme to allow constables to rise to the rank of inspector in just three years, while foreign candidates could be able to apply for chief constable roles for the first time.
A recent survey by the University of the West of England found that just over half of police officers said they would consider looking for alternative employment as a direct result of concern over the proposals.
Dr James Hoggett, who led the research, said: "The study showed that proposed changes and those currently being implemented are causing significant levels of uncertainty and concern amongst officers on the ground."
The online ballot by the Police Federation, which has over 130,000 members, was conducted by Electoral Reform Services and was open to all officers from police constable to chief inspector.
It is illegal for police officers to take industrial action - the last official strike was believed to be in 1919.
The federation will seek a change in the law if there is a yes vote.