The decision to send UK police officers to train their counterparts in Libya was "naive and insensitive", the chairman of the Police Federation said.
Paul McKeever said the scheme would spark anger over the killing of Pc Yvonne Fletcher.
She was shot 25 years ago outside the Libyan embassy but the Government has allegedly agreed her killer would not be tried in Britain.
He said: "Whilst it may be customary for countries to look to the UK police to provide expertise and training I find it incredible that the Foreign Office has been so naive and insensitive imposing this particular request on the National Policing Improvement Agency.
"This will further anger and disgust rank and file officers who believe Libya should and could be more proactive in securing the arrest of Pc Fletcher's killer. This one way traffic, where we do all the giving and they just take, must stop."
The National Policing Improvement Agency (NPIA) refused to name individual forces involved, but a spokesman confirmed the officers came from across the UK.
According to The Daily Telegraph, the Metropolitan Police was one of the forces involved.
The NPIA spokesman said there had been three training projects in Libya in the last 12 months involving UK officers.
These covered leadership, strategic planning and forensics. No serving officers are currently in the country.
As part of the scheme, Libyan officers have also visited Britain in the past year to view our forensic methods, he said.
