An Islamic State terrorist has been found guilty of plotting to behead the Prime Minister. 

Naa’imur Zakariyah Rahman, 20, appeared at the Old Bailey on Wednesday charged with preparing acts of terrorism over his suicide attack plan on Downing Street.

The 20-year-old was arrested last year along with another man, Mohammed Aqib Imran, following raids in London and Birmingham.

Imran was charged with planning to travel abroad, either to Libya or Syria, in order to engage in terrorism.

Rahman had believed he was corresponding online with Islamic State (Isis) while planning the attack, but was in fact talking to members of the security services pretending to be from the terrorist group, the Old Bailey was told during his trial. 

Messages read out in court from the Telegram app show Rahman wrote on September 14 last year: “Can you put me in a sleeper cell ASAP? I want to do a suicide bomb on parliament. I want to attempt to kill Theresa May.”

The next day, he said: “My objective is to take out my target. Nothing less than the death of the leaders of parliament.”

Rahman was arrested in London on November 28, shortly after the last of a number of meetings with undercover police officers posing as terrorists.

He was arrested following a joint operation by MI5, the UK’s counter-terrorism security service, and police.