Policing and security costs for the G8 conference in Co Fermanagh next month are running at an estimated £50 million, it has been revealed.
As security chiefs in London and Belfast prepare for the summit at Lough Erne near Enniskillen, the body in charge of the finances said the PSNI has been told it must obtain a written guarantee that any expenditure can be recouped.
"PSNI expenditure in support of the G8 policing operation is likely to cost in the region of £50 million," said Sinn Fein MLA Gerry Kelly, who chairs the Northern Ireland Policing Board's resources committee.
He added: "Whilst there have been discussions between the PSNI, the Department of Justice and Government departments around arrangements for the PSNI costs to be met in full, assurances and timescales for refund have not been confirmed in writing."
The PSNI has an annual budget of £1.2 billion but has been tasked with making major efficiency savings in recent years. Mr Kelly said he was concerned normal policing could be adversely impacted if the PSNI has to carry the costs for the G8.
"As accounting officer the Chief Constable must be provided with a written assurance that these monies will be promptly refunded so that there is no knock-on impact for operational budgets," he said.
"The Policing Board will be raising the matter with the Justice Minister and the Secretary of State and the Chief Constable will be asked for his assessment of discussions on this issue at the June Board meeting."
Eight of the world's most powerful leaders including US President Barack Obama, Russian premier Vladimir Putin and German Chancellor Angela Merkel will jet into Northern Ireland for the two-day conference on June 17 and 18.
A ring of steel has been erected to keep the thousands of anti-capitalist protesters away from the luxury golf resort and roads into and out of the area will be closed.
Much of Northern Ireland is expected to go into lockdown. An extra 3,600 specially trained public order police officers are being drafted in to help bolster the 7,000 PSNI members and the military will provide air security for VIPs. Two private security firms have also been hired to help with searches and perimeter security.