Cross-Channel and domestic rail fares could be cut after a regulator announced proposals to lower fees for train operators running services between London St Pancras and the Channel Tunnel.

The Office of Rail and Road (ORR) said the amount paid by Eurostar and Southeastern to use the High Speed 1 (HS1) line for the five years from April 2025 should be cut by 7.7% and 10.8% respectively.

For freight users, charges should be cut by 66%.

HS1 is used by Eurostar trains to Paris, Brussels and Amsterdam; domestic Southeastern services between London and Kent, and within Kent; and freight trains heading to and from the Channel Tunnel.

Demand for seats on Eurostar services has soared since the end of coronavirus travel restrictions despite an increase in fares.

HS1 is owned by a group of private investors.

The ORR set out its proposal to lower access charges after carrying out a review of the company’s spending plans.

It found the company has produced “good quality” plans but there are “opportunities” for “further efficiency”, resulting in savings to its passenger and freight train operator customers.

ORR director for planning and performance Feras Alshaker said: “The High Speed 1 line is a vital connection between the UK and continental Europe, and makes a crucial contribution to the UK economy, supporting growth.

“It is important that it continues to be a resilient, high-performing network for both passengers and freight users.

“The detailed scrutiny and challenge we’ve applied to HS1 Ltd’s plans should see the costs of operating on the line reduce significantly, giving savings for both international and domestic operators over the next five years, with benefits for passengers and freight users.”

HS1 Ltd chief strategy and regulation officer Mattias Bjornfors said: “We welcome the ORR’s support for our plan for the next five years and acknowledgement of our success during the current control period.

“Our plan for 2025-2030 included several proposals to reduce charges for freight and transport operators which have been accepted.

“HS1 has already driven down costs and improved performance by investing in innovative technologies and working with partners to make multimillion-pound savings and reduce train delays.”

He added: “We anticipate further services on the HS1 route will lead to lower charges for operators.”