Eurostar staff start first of four strikes
The first of four separate Eurostar strikes by staff from two unions gets under way on Friday but the impact on services is set to be limited.
Members of RMT will go on strike from 12 to 15 August, and 27 to 29 August during the bank holiday weekend.
TSSA staff plan to strike on 14 and 15 August, and 28 and 29 August.
Eurostar has made some modifications to its weekend timetable to ensure "all passengers will be able to travel", with eight services cancelled.
Eurostar said this represents just 4% of its services between Friday and Monday.
Two scheduled trains will not run on Friday. Services on Saturday will run as planned, and four services have been cancelled on Sunday and two on Monday.
A Eurostar spokesman said: "We are aware of the plans for strike action and our focus has been seeking a joint resolution whilst planning to provide a good service for our customers."
The cancelled services on Friday are the 08:04 service from London to Brussels, and the 12:52 departure from Brussels to London.
On Sunday the 14:13 and 16:43 trains from Paris to London and the 10:01 and 16:31 trains from London to Paris will not run.
On Saturday none have been cancelled, while on Monday the 07:55 train from London to Paris and the 08:43 train from Paris to London have been cancelled.
"We have made some small changes to our timetable with all passengers due to travel on affected trains notified in advance, to allow them to change their booking to another train on the same day," Eurostar said.
Eurostar runs services between London and mainland Europe, and the walkouts coincide with the Assumption Day holiday in France and Belgium on 15 August and the 29 August bank holiday in England, Wales and Northern Ireland.
Transport Secretary Chris Grayling has said the actions "feel like an excuse to be militant".
But the RMT says the dispute concerned unsocial hours and duty rosters for about 80 train managers. It says Eurostar has failed to honour an agreement from 2008 over conditions for their staff.
General secretary Mick Cash said: "Our train manager members at Eurostar have a heavy commitment to shift work and unsocial hours and are sick and tired of the company's failure to honour agreements."
Meanwhile Manuel Cortes, TSSA union general secretary, said there was still a "window of opportunity" to solve its dispute in talks with management on Friday.
"This is a long-standing issue and there is still time to resolve it if common sense prevails on Friday. No one wants to see disruption at holiday times and we will be working for a peaceful solution."