Former British MP George Galloway has won permission to sue Google over a broadcast of a loyalist protest in which he was described as a “tramp” who supported terrorist beheadings.
The action at Belfast's High Court is believed to be the first of its kind in Europe over comments broadcast on YouTube.
Victims campaigner Willie Frazer is also being sued for allegations made at a picket outside the Ulster Hall in Belfast as Mr Galloway appeared at a public speaking event in August 2014.
Protests outside the event, billed as Saturday Night with George Galloway, had centred on his earlier reference to Bradford being an Israeli-free area.
Mr Galloway alleges Mr Frazer slandered his name with a series of vitriolic, abusive, sectarian and wholly untrue speeches.
The material allegedly broadcast by Mr Frazer on YouTube, which is owned by Google, was said to have been viewed 17,000 times.
Mr Galloway, a former MP for Bradford West, wants to serve libel and harassment proceedings on Google at its US headquarters.
The Court today upheld his right to continue with his action.
Mr Galloway's claim for damages is expected to be heard in full later this year.
In a statement Mr Galloway said: "Defeat in this case would have been financially ruinous to me which is of course what the corporations count on in such cases."