The Ministry of Defence (MOD) "cannot determine a realistic timescale" for the introduction of the Ajax armoured vehicle into operational service, a minister has said.
General Dynamics UK was contracted to supply the British Army with 589 Ajax vehicles - they were originally due to enter service in 2017 but the troubled programme is now more than four years behind schedule.
General Dynamics UK has received more than £3bn and as of June this year, only 26 vehicles had been delivered.
In 2021, ministers publicly acknowledged that the programme was in trouble and have been making regular updates to Parliament on the situation.
Issues with the programme have included excessive noise and vibration problems, which have left dozens of troops needing urgent hearing assessments after taking part in trials on the vehicles.
Answering a question from Labour’s shadow defence secretary John Healey about delivering the Ajax programme on time and within budget, defence minister Alec Shelbrooke said: "The Ministry of Defence continues to work with General Dynamics to resolve the noise and vibration problems on Ajax while protecting the taxpayers' interests.
WATCH: Timeline of the troubled Ajax programme so far.
"As acknowledged by the Infrastructure Projects Authority the project remains within its approved budget and General Dynamics are required to deliver to the terms of the £5.5 billion firm-priced contract.
"We will not accept a vehicle until it can be used safely for its intended purposes and until long-term solutions to the noise and vibration problems have been found, we cannot determine a realistic timescale for the introduction of Ajax into operational service."
Earlier this year, a Whitehall spending watchdog warned that problems with the troubled programme are so deep-rooted that they may never be resolved.
In a report, the National Audit Office (NAO) said the £5.5bn project was "flawed from the start", with the Ministry of Defence (MOD) failing to understand the scale and complexity of the work it was undertaking.
It said delays to the programme could now jeopardise plans to restructure the Army around a new generation of digitally-enabled armoured fighting vehicles.