Cuts to police numbers have "likely contributed" to a rise in serious violent crime, according to a leaked Home Office document.
The paper prepared by officials as part of preparations for the new strategy being launched by Home Secretary Amber Rudd said offenders may have been "encouraged" by the lack of police resources and fall in charge rates.
The document, obtained by the Guardian, risks embarrassing ministers including Ms Rudd who have insisted that a decline in the number of officers could not be linked to a rise in violent crime.
The paper, entitled Serious Violence; Latest Evidence On The Drivers, said: "Since 2012/3, weighted crime demand on the police has risen, largely due to growth in recorded sex offences.
"At the same time officers' numbers have fallen by 5% since 2014.
"So resources dedicated to serious violence have come under pressure and charge rates have dropped. This may have encouraged offenders."
It was "unlikely to be the factor that triggered the shift in serious violence, but may be an underlying driver that has allowed the rise to continue".
A highlighted box summarises the point: "Not the main driver but has likely contributed."
The document said that it was unlikely that "lack of deterrence" was the catalyst for the rise in serious violence and noted that "forces with the biggest falls in police numbers are not seeing the biggest rises in serious violence."
Between 31 March 2010 and 2017, police officer strength fell in the 43 UK forces from 143,734 to 123,142.
Shadow home secretary Diane Abbott said: "The Government's own analysis seems to suggest that cuts to police officer numbers has had an effect in encouraging violent offences.
"If true this blows apart the Tories' repeated claims that their cuts have had no effect.
"Cuts reduce police effectiveness and their ability to apprehend criminals. It also undermines the reassurance and deterrent effect that a police presence can have.
"If the Government's own serious violence strategy accepts that police cuts have had an effect, why can't the Government itself?
"The Tory Government should halt all further cuts to the police. Labour in government will recruit 10,000 additional officers to tackle surging gun and knife crime."
The Home Office said it would not comment on a leaked document but ministers have denied a link between police numbers and the rise in violent crime.
Ms Rudd used a Sunday Telegraph article to say: "In the early Noughties, when serious violent crimes were at their highest, police numbers were rising. In 2008, when knife crime was far greater than the lows we saw in 2013-14, police numbers were close to the highest we'd seen in decades.
"So while I understand that police are facing emerging threats and new pressures - leading us to increase total investment in policing - the evidence does not bear out claims that resources are to blame for rising violence. "
Communities Secretary Sajid Javid maintained that position, telling BBC's Andrew Marr Show: "For anyone to suggest that this is caused by police numbers, it is not backed up by the facts."
Policing Minister Nick Hurd acknowledged that the system was "stretched" but told the BBC it was "categorically not the case" that a reduction in numbers was behind the rise in violent crime.