A supporter of the Islamic State terror group has pleaded guilty to plotting to bomb St Paul’s Cathedral and a hotel in central London.

Safiyya Amira Shaikh, from Hayes, Middlesex, admitted preparation of terrorist acts and dissemination of terrorist publications at a hearing at the Old Bailey.

The 36-year-old, who was born Michelle Ramsden and converted to Islam in 2007, was arrested after asking an undercover police officer to supply bombs.

The charge states Shaikh made contact with someone who could prepare explosives and went on a reconnaissance trip to scope out the historic cathedral and a hotel as locations to plant bombs.

She prepared the words of a pledge of allegiance to the group, also known as the so-called Isis or Daesh, between August 2019 and October 2019.

The 36-year-old has pleaded guilty to plotting to bomb St Paul's Cathedral. Credit: PA

She also shared terrorist documents via groups using the Telegram messaging app over the same period.

The court heard Shaikh had scoped out St Paul's security and looked for the "best place" to plant a second explosive device.

The defendant, who wore black robe, spoke quietly as she entered her guilty pleas before Mr Justice Sweeney at the Old Bailey on Friday.

The facts were not opened in court, but according to a prosecution case summary, Shaikh had stated her main aim was to kill as many people as possible in a suicide attack on St Paul's.

She only confided her plan to two people, the online explosives expert and his wife who she handed her bags to, unaware that they were undercover officers.

In encrypted chat with an undercover officer last August, the defendant said that she would "rather die young and get to Jannah (paradise) quickest way possible".

She also stated: "I always knows I wanted to do something big....killing one kafir (infidel) is not enough for me."

Shaikh expressed a desire to target a church or somewhere "historical" on a day like Christmas or Easter to "kill more", according to the case summary.

In September last year, she revealed her plan to stay in a hotel near St Paul's then check out the cathedral and "take photos like a tourist".

The court heard Shaikh had scoped out St Paul's security. Credit: PA

On September 24 last year, she met the fake explosive expert's wife in Uxbridge to hand over her bags.

Then on October 13, the female undercover officer cancelled a second meeting and police forced their way into Shaikh's flat to arrest her.

In a police interview, the defendant, who claimed benefits, admitted posting extremist material and the plot, although she said she may not have gone through with it.

Mr Justice Sweeney ordered pre-sentence reports ahead of sentencing on May 12.

The judge ordered the defence should serve any psychiatric report by April 3.