The SAS was on standby last night after more than 100 London gun police officers fired weapons in protest at a colleague’s murder charge.
The military was on standby after the force was left in “skeleton” display as officers turned in their blue authorization cards.
It was understood that only one in seven firearms units was deployed to combat terrorism.
Firearms officials elsewhere in the UK refused to travel to London in solidarity with Met colleagues.
It follows the indictment of an officer, previously only named as NX121, over the murder of Chris Kaba, 24, last week.
The rapper was shot dead in Streatham Hill, south London, in September last year.
The Met confirmed yesterday that the Ministry of Defense had agreed to a request to provide “counter-terrorism support where required”.
It said: “Armed Forces personnel are not deployed for routine police operations.”
Meanwhile, Interior Minister Suella Braverman ordered a review of the armed police.
She said: “They must not be afraid of ending up in the dock for discharging their duties.”
The Met Commissioner called for a redesign of accountability mechanisms so that officers who use force in the line of duty and in accordance with their training are not normally prosecuted.