Greville Janner has arrived at Westminster Magistrates' Court in Britain to attend a child sex abuse hearing, after failing to turn up earlier.

Wearing a baseball cap, the 87-year-old peer was driven into a side entrance in the rear of a grey Toyota Avensis.

His initial no-show had led a judge to threaten an arrest warrant.

Lord Janner, who has dementia, faces 22 charges relating to offences alleged to have taken place between the 1960s and the 1980s.

Friday's hearing at a packed courtroom initially got under way without Lord Janner, even if he had been ordered by a High Court to attend.

Much of the morning was taken up by his lawyers arguing that a court appearance would be too distressing for the peer. They sought to have him appear via video-link, citing his poor condition.

But the argument was rejected by District Judge Emma Arbuthnot, who, amid the legal wrangling, appeared to lose patience.

She told the defence lawyer to "stop messing around" and added: "I'm warning you that as time progresses I'm going to turn to the prosecution and say, 'Lets get a warrant to have him arrested. Let's not waste time.'"

The peer, whose full title is Baron Janner of Braunstone, was a QC and then MP for Leicester West until his retirement from the House of Commons in 1997 when he joined the Lords.

He has been on a leave of absence from the Lords since October 2014 as a result of his illness.

Earlier this week, his lawyers had sought to prevent Lord Janner from having to attend the hearing, on grounds of his poor health and the risk of an injury.

But High Court judges ruled on Wednesday that public interest outweighed any personal distress that might be caused to him.