The Home Office said they will not be refused entry based on MI5 security advice but the government department can deny them visas on the grounds that their "presence in the UK would not prove conductive to the public good Press TV reported.
The Home Office also said MI5 has summoned all members of its spying army back to Britain and all its 3,800 agents will be watching the 2012 Olympics during the games.
The operation, which would be MI5’s biggest since the Second World War, will see the agents involved in different tasks including counter-espionage turn their focus exclusively on threats from terrorists.
This comes as the government has so far failed to make any announcements on a proven terrorist risk during the games.
The spy agency has also set up a new surveillance and intelligence gathering system specifically for the games, The Independent reported.
The paper said as part of the operation, the MI5 will monitor more than 540,000 people as well as those it deems as militant groups.
The people the agency would be monitoring even include athletes, their families and officials of the participating countries.
A potential move against Iranian officials, athletes, or their families based on unfounded human rights accusations would be a rerun of the denial of entry visas to Iranian youth who had registered for the London Skill 2011 competitions.
British officials prevented Iran from taking part in the industrial control and CNC routers sections of the event, which was part of the World Skills International biannial contests, last October while delaying entry visas to Iranian contestants in eight other sections until the very last moment.
Earlier in April, London had also denied entry visas to Iranian publishers who were set to attend the London Book Fair 2011 back in April.
British officials resorted to ludicrous justifications to deny visas to all but two Iranian publishers, at the time, saying they could not make sure the publishers could afford the money to return back home.
Source : Afghan Voice Agency (AVA), Kabul