The Government is expected to sell off the Channel Tunnel high-speed rail link as part of its programme to reduce the £167 billion deficit in public funds.

The 67-mile link from London St Pancras International to Folkestone, Kent, was completed in 2007 at a cost of £5.8 billion but is expected to fetch only £2 billion.

It is possible that the link, which is currently owned by the state-owned London & Continental Railways, will fall into the hands of non-British owners.

It is also likely to open up the prospect of more train operators using the link, where international services are currently provided by Eurostar and the only domestic services are provide by South Eastern's high-speed Javelin trains.

Meanwhile it is unlikely that there will be fair competition between road and rail transport while the Highways Agency remains firmly in the public sector as an executive agency of the Department for Transport and has a voracious appetite for taxpayers' cash.

Some rail campaigners insist that no sale of the rail link should take place until the Highways Agency is privatised.

They also say the proceeds of the sale should be invested in plans to establish a high speed rail link to Scotland and the north.

Network Rail has a contract to maintain and operate the link until 2015 and could bid for the link, which includes St Pancras, Ebbsfleet and Stratford International stations, but is under pressure from the Government to reduce its costs.

Groupe Eurotunnel, which runs the Channel Tunnel itself, may be another potential buyer.

Network Rail which received nearly £4 billion of taxpayers' money a year has a contract to maintain the link until 2015.

Information from Andrew Long.