Prime ministers have always been terrorist targets, though Downing Street is now well protected by fortified gates and armed police officers.
Naa'imur Zakariyah Rahman, 20, and Mohammed Aqib Imran, 21, were driven into Westminster Magistrates' Court in a security van this morning after being charged with planning terror attacks.
On Tuesday, MI5 chief Andrew Parker told lawmakers that British intelligence has foiled nine terror plots in the past 12 months.
This year in the United Kingdom there have been five terrorist attacks.
Police said the pair had meant to launch some sort of improvised explosive device at the prime minister's residence and kill Theresa May in the chaos that followed the explosion, Sky News reported. When asked about his nationality in court, Imran said he was Bangladeshi British. The recording would have given Imran greater credibility with the terrorist organization, the document said.
It also said in a statement that the men were arrested by its Counter-Terrorism Command on 28 November.
They remain in custody and are due to appear in court on Wednesday, local time.
Bomber Salman Abedi killed 22 people when he blew himself up outside an Ariana Grande concert in Manchester.
Officials said it was the 22nd foiled plot since March as hundreds of terrorist suspects remain under investigation.
"It is in essence an extreme Islamist suicide plot against Downing Street".
After the meeting, the prime minister's spokesman said: "The prime minister led thanks to the tireless work of staff at MI5 to combat the unprecedented terrorist threat".
Britain has seen five terror attacks this year, which killed 36 people and injured more than 200 others.