The proposals are intended to protect London’s finance district and its skyscrapers from a terrorist attack.
MI5 and counter-terrorism police have proposed to install the manned checkpoints, rising street bollards and crash-proof barricades.
The last time manned checkpoints were used was in 1992 following the IRA’s bombing of Baltic Exchange.
A Corporation of London report said they “had identified that the area was highly sensitive to… a hostile vehicle-borne security threat”.
The new proposed ring would border Liverpool Street, the Bank of England and Fenchurch Street, which is home to some of the council’s most renowned skyscrapers.
Will Geddes, founder of International Corporate Protection, said: “Although we’ve seen of late ‘lo-fi type’ attacks, like the Berlin Christmas market where a lorry that was hijacked and driven into a crowded area, we cannot discount the type of attack that will include a large truck packed with explosives.”
The new proposal could be fully implemented by 2022.