The Road Traffic (Amendment) Act (Northern Ireland) 2016 lowered the drink-driving limit and allowed for police officers to conduct random roadside breath tests.

Prior to the legislation, police needed reasonable suspicion before asking a motorist to take a breath test.

However, PSNI breathalysers are not capable of accurately testing drivers for the new limit of 9mg per 100ml for learner and novice drivers - substantially stricter than the new 22mg per 100ml limit for standard drivers.

No manufacturer has produced roadside breathalysers capable of testing the lowest levels of nine micrograms.

In a statement, the PSNI said: “A new testing process has been taken forward by the Home Office, with manufacturers encouraged to participate in the production of new breath-testing equipment.”

A spokesperson for the Home Office added: “It is for manufacturers to market their device and the police to decide when to procure. The Home Office only approves equipment for police use and do not have any involvement in decisions about lowering drink-drive limits.”

Alliance MLA John Blair, a member of the Policing Board, told BBC News: “We must ensure the PSNI is using the most up-to-date equipment and any ambiguity around this is not acceptable.

“Not only is this yet another item to add to the list of outstanding issues for the newly reconstituted Policing Board, but again demonstrates how the lack of an executive is damaging Northern Ireland.

“Clearly this issue will be best addressed with a justice minister in place, working alongside the Policing Board and other relevant bodies to press the Home Office for change.”