A failed asylum seeker who planted a fake stick of dynamite outside MI5 headquarters on New Year's Day has been jailed for two-and-a-half years.

Brazilian national Julian Valente Pereira, 33, left the fake bomb outside Thames House in central London on January 1 at 3.02pm, a day after he was handed a deportation notice.

Pereira came to the UK with permission to work in July 2018 before claiming asylum, which was rejected.

Shannon Revel, prosecuting, had said the Brazilian wanted 'maximum attention' on his complaints against the Home Office after a long-running failed bid to stay in Britain.

CCTV footage showed Pereira stuffing paperwork about his immigration case through the MI5 building's doors before taking the fake explosive from his bag and throwing it on the pavement.

A fuse appeared to hang from the top of the brown cylinder, which a bomb expert found was made from rolled-up A4 paper, brown masking tape and string.

London played host to a New Year's Day parade the same day.

Pereira was living in an asylum hotel in Uxbridge, west London, and had been diagnosed with bipolar disorder and schizophrenia, a court heard.

He said the device he laid would not have been mistaken for an explosive.

But after trial he was found guilty in February of placing an article with the intention of inducing another to believe the item was going to explode.

At the Old Bailey on Friday, Judge Mark Lucraft KC, sentencing, jailed Pereira for two years and six months.

The judge said the defendant 'may well' be deported from the UK.

Judge Lucraft noted police concerns at the time that the fake dynamite was a 'genuine explosive' and that dealing with the incident 'diverted them from other things'.

Though officers found it to be a hoax within an hour, concerns remained the dummy device could have been 'a diversionary tactic in preparation for another incident elsewhere', the judge added.

He told the defendant: 'You are of good character, demonstrating some remorse for what you did, expressing regret and sorrow for your actions that day.

'You accept now that what you did was foolish.'