Passengers on the service from St Pancras International will be able to reach the French Mediterranean port city in just over six hours.
Officials say the seven men and a woman detained in the Paris and Lyon areas are not suspected of links to the Paris attacks of January 7th to 9th.
Two minors were among those arrested near Lyon on suspicion of recruiting young women to fight in Syria.
Man started his ten months of harassment after the woman ended their relationship - he wanted her to thank him for doing up their flat.
Pro-democracy and minority groups protested PM Recep Tayyip Erdogan's visit to meet with Turkish expats ahead of presidential poll.
Officials want the European Parliament to strip National Front leader of MEP's immunity with a view to pursuing her over a remark about Muslims.
The controversial plans for a 26-billion-euro high-speed rail link between the two countries face opposition from environmental activists.