The Chief Coroner has called for armed police to be stationed at all gates into Parliament in the wake of the Westminster terror attack.
Mark Lucraft QC raised a string of "concerns" after ruling that four members of the public and PC Keith Palmer were unlawfully killed by terrorist Khalid Masood.
On March 22 last year, Masood, 52, mowed down pedestrians on Westminster Bridge, killing four and seriously injuring 29, before stabbing unarmed Pc Palmer to death at the Palace of Westminster.
On Thursday, Mr Lucraft issued a detailed report on "action to prevent future deaths", including stationing armed guards at the gates.
He wrote: "It was a matter of concern that, at the time of the attack, one of the most vulnerable and public entrances to the Parliamentary Estate was not protected by armed police.
In the autumn, the Old Bailey inquest heard how Masood stabbed unarmed Pc Palmer, who was guarding the gates of the Palace of Westminster with other unarmed colleagues.
Masood's rampage was stopped by a close protection officer, identified only as SA74, who shot him three times with a Glock pistol.
The other victims were American tourist Kurt Cochran, 54, retired window cleaner Leslie Rhodes, 75, mother-of-two Aysha Frade, 44, and Romanian designer Andreea Cristea, 31.
- Press Association