Rahman, 20, from north London, is accused of planning to bomb Downing Street's security gates and then attack the Prime Minister in the ensuing chaos.
The plot was revealed to the British cabinet on Tuesday by Andrew Parker, the head of the security service MI5, who also told ministers that security services had foiled nine terrorist attacks in Britain in the past year. When asked about his nationality in court, Imran said he was Bangladeshi British.
An Islamist terror plot to assassinate British Prime Minister Theresa May by detonating an explosive device to storm into her Downing Street office has been foiled by the country's security services, media reports said today. Four of them were claimed by the Islamic State group. Imran said he was "Pakistani British".
They have been remanded in custody to appear before the Old Bailey court in the city on December 20. Anderson said the Manchester bombing attack, which killed 22 people at a music concert in May, could have been stopped "had the cards fallen differently". The report said the agency, MI5, had twice received intelligence on Abedi "whose significance was not fully appreciated at the time".
Image Downing Street has tight security
Britain has seen five terror attacks this year, which killed 36 people and injured more than 200 others.
"There are now well over 500 counterterrorism investigations, involving more than 3,000 subjects of interest - along with a growing pool of more than 20,000 individuals who have previously been the subject of terrorism investigations", the statement said.
The pair was arrested in London and Birmingham on November 28 by the Metropolitan Police Counter Terrorism Command.