There will be two trains a day at first, and the journey will take just under four hours, according to the Evening Standard.
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Over three million people a year travel by air between London and Amsterdam, and the new service will challenge airlines like Easyjet and British Airways.
A direct route to Rotterdam is also said to be in the final stages, according to Kent Online.
The company this week unveiled a preview of its new e320 trains set to run between London and Brussels over the next 18 months. The new fleet has 20 per cent more capacity than present Eurostar services, and the trains have been operating on the London-Paris route since November 2015.
On its website, Eurostar said: "With its new e320 trains, which are interoperable and can operate on the European high-speed network beyond the UK, France and Belgium, the company is in the final stages of preparation for the launch of its new direct service to Amsterdam and Rotterdam.
Nicolas Petrovic, Chief Executive of Eurostar, said: "The introduction of the e320 on the Brussels route marks an important milestone and step change in the travel experience for our customers.
"With demand for high-speed rail over plane on the increase, we are now gearing up to expand our reach to the Amsterdam and Rotterdam.
"The launch of our new direct service on this high volume route represents a major growth opportunity for our business".
Marjon Kaper, Managing Director NS International, said: "Today is a very special day for NS and all the partners, because the start of services with the new train to Brussels literally brings the "Amsterdam Route" closer.
"We see a lot of interest and potential for the high-speed connection between these top destinations – London for visitors from the Netherlands and Amsterdam and Rotterdam as the new hotspots for the British traveller."