International rail services from London to France and other European countries are set to grow dramatically in coming years.

Sir Richard Branson’s Virgin is among operators seeking to take on Eurostar in offering cross-Channel routes to European capitals and other cities.

In a major development, Stratford International Station is set to be opened up for services to the Continent.

Here are the key details:

The building of Stratford International was completed by 2006 but it has never been used for services through the Channel Tunnel, not even during the 2012 London Olympics.

Under plans, being driven forward by Lord Sadiq Khan, international services could stop at the east London station within four years.

One in three trains to and from France could halt in future at Stratford International.

The proposals still need the backing of the Government, the French authorities and for an operator to decide that running the services makes financial sense.

However, Chancellor John Healey may give approval for a Business Rate Retention Zone, to fund the scheme, possibly as early as the Budget on Wednesday October 28.

Operators are also looking into other possible destinations in Germany and Switzerland.

Virgin is exploring stopping international services at Stratford as part of its plans from 2030 to take on Eurostar which so far has declined to use the east London station.

Stratford International could in future decades be used as a hub for rail services from other parts of Britain to link up with the international network so millions more people could head to the Continent by train rather than fly.

Stratford International Station has a mothballed international section, including two platforms, as well as two used by Southeastern to run services to Kent.

It is understood that the international part of the station could be brought into use at a cost of around £20 million.

Part of the programme would involve putting in shops, cafes and other facilities.

Some of the original signs in French, installed many years ago, are still up.

The exact route for passengers through the station would have to be developed, from arrival, to ticket scanning, going through security with bag checks and into a waiting area.

Stratford is expected to be used as a stop, adding five to eight minutes to a European journey, rather than a new London terminal to rival St Pancras International.

The new international station would have capacity for 250-300 passengers at a time, compared to 2,500-3,000 per hour at St Pancras.

More operators running international services to the Continent will mean competition for Eurostar for the first time.

It could drive down the cost of some tickets, particularly for standard services.

But there could also be more luxurious travel on offer, at a higher price, as competition leads to more innovation.