The government has paused all testing of Ajax armoured vehicles after another soldier was injured during safety trials.
Three separate investigations are currently being conducted after around 30 soldiers became ill from noise and vibration during a training exercise in November.
Twenty-three vehicles used on the exercise were already suspended for use due to the injuries, with the results of inspections on them to be published in the New Year.
In a written statement to Parliament, defence minister Luke Pollard said the latest report of a soldier becoming ill from vibration came during additional safety trials intended to provide more information for the investigations.
The defence minister said the soldier did not require hospitalisation, and the vehicle they were in – which is not one of the 23 already suspended – is undergoing a “thorough investigation”.
He said: “This additional report of an injury is a serious concern to me so, out of an abundance of caution and to ensure the safety of our personnel, I have directed a pause on all Ajax trials.”
“This is in addition to the ongoing pause for training and exercising.”
He said he would assess if trials could be restarted in the New Year.
The minister added that investigation teams must be given “time and space required to ensure all information and evidence is considered” and that he had met with the vehicle’s builder General Dynamics last week.
Responding to the announcement, Welsh Secretary Jo Stevens told the BBC the most important thing was to “make sure that equipment that’s being supplied is safe”.
“The government has undertaken a review,” she said.
“There are several reviews going on into the problems that have been reported.
“I can’t really comment whilst those reviews are underway, but I’m very conscious that General Dynamics is a very important employer in Wales, and particularly in the constituency in Merthyr Tydfil.
“So we’ll wait and see what happens with the review. But absolutely paramount to this is that the equipment that is provided is safe for use.”
The multi-million pound Ajax vehicles, made in Merthyr Tydfil by General Dynamics, were originally due to enter service in 2017, delivering 589 vehicles.
The £6.3bn programme has been beset by problems and repeated delays, as noise and vibration have injured soldiers who have tested the vehicles.
Pollard previously said he was “disgusted” that soldiers were injured after he had been assured the armoured vehicles were safe.
There are currently three investigations ongoing, by the Defence Accident Investigation Branch, the Army’s safety investigation team and a ministerial review.
Regular meetings have also been held between the minister, chief of general staff, the Army and officials, according to the statement.
The BBC understands General Dynamics representatives have also met with backbench MPs in recent days.
MPs have previously raised concerns about uncertainty around the programme having an impact on jobs in their constituencies.
Pollard said findings from the investigations into Ajax vehicles would impact on decisions in the UK government’s defence investment plan.
Earlier this week Defence Secretary John Healey said “programmes beset by deep-running failures, such as Ajax” had delayed the publication of the plan, which was due in the autumn.
It was supposed to map out the spending needed to overhaul the armed forces, but will now be delayed to 2026.
