Ministers have issued an emergency recall of 120,000 body armour plates used by the British military, amid accusations from Labour that the Conservatives failed to safely renew basic protection for troops during their time in office.

Testing discovered microscopic cracks in ageing enhanced combat body armour (ECBA) which was supposed to be swapped out in 2023, but whose replacement was delayed by four years to make savings by the previous government.

Luke Pollard, the armed forces minister, wrote to chiefs across the forces at the end of last week to order the emergency replacement of the light armour, which is still widely used in the navy. It is also used by the army in low-threat environments.

Defence ministers “will not tolerate this risk”, Pollard wrote when he ordered the bulletproof plates to be immediately recalled. He added that a replacement process that had been due to complete in 2027 would now be accelerated.

Labour insiders also blamed the Conservatives for “leaving troops vulnerable with defective body armour” and argued the situation was similar to the Covid-19 crisis when “the Conservatives left NHS workers unprotected when they failed to provide PPE”.

Doctors and nurses complained there were not enough protective gowns, gloves and masks at the start of the pandemic, prompting a desperate, chaotic rush of orders. The comparison demonstrates Labour’s eagerness to highlight the body armour issue.

“It is clearly not acceptable for any of our armed forces personnel to be concerned about the quality of such fundamental safety equipment,” Pollard said in his letter.

ECBA was first introduced more than 30 years ago and includes small front and back plates over the heart, but it was not popular with British troops on deployment in Iraq and Afghanistan because it offered limited protection.

It has since been replaced for frontline tasks in the army but is still used in the navy and by marines because newer, heavier flak jackets are dangerous if the wearer ends up in water. They are also used by guard troops and in training, and as side plates with newer Osprey and Virtus flak jackets.

About one in 10 ECBA plates are believed to be defective. Once recalled, they will be tested to see if they remain fit for use. As a result, ministers hope it will be possible to swap out the armour without incurring extra cost, by testing it promptly and returning it back to service if deemed safe.

Although Labour has promised to raise defence spending from its current level of 2.33% of GDP to 2.5%, ministers have repeatedly declined to put a date on when the UK would meet that commitment.

“​We are working hard to set the path to 2.5,” Keir Starmer, the prime minister, said in Brussels on Monday.

A strategic review, run by three independent advisers headed by George Robertson, a former Nato secretary general, is expected to conclude internally in mid-February and to be published before Easter, though it may take longer. It is unclear how far its release will be accompanied by spending announcements, and a commitment on the overall defence budget may be announced at the Nato summit in June.

The MoD said ECBA had been “suspended in all but unavoidable circumstances” as a precaution after regular testing had identified an issue. “This government will not accept compromises when it comes to the safety of our people,” an MoD spokesperson said.