However, the gradual expansion of the service will only happen if a four-country treaty, involving Britain, France, Belgium and the Netherlands, is signed regarding border controls.

At present, Eurostar passengers from the Netherlands must disembark at Brussels South to pass through a security check and pass control before boarding a train to London. This means the Amsterdam - London trip takes around five hours compared with about four hours in the opposite direction.

NS says it hopes the direct Amsterdam - Rotterdam - London services will start this spring.

According to NS, rail currently has a 23% share of the Amsterdam - London market, and this is expected to increase significantly when passengers no longer have to change trains in Brussels.

NS says if the five daily services are successful, the Eurostar train frequency might be increased even more.