A group of MPs have called on the government to reduce the top speed of the HS2 rail network.

Members of the House of Commons Environmental Audit Select Committee stated this would have greater benefits for the environment, although they acknowledge journey times would also be affected. The group warned current proposals threaten biodiversity across the entire stretch of the route. 

As things stand, the rail service is set to run at 350 km/h, with the possibility of the line being 'future-proofed' over the coming years to potentially achieve speeds of up to 400 km/h. However, committee members stated the trains should be restricted to just 300 km/h.

This would still allow the service to journey from London to Manchester in around one hour and eight minutes, a full 60 minutes faster than the current timeframe experienced on the West Coast Mainline.

In its report, the committee stated: "The government should examine the scope for requiring a maximum speed for the trains until electricity generation has been sufficiently decarbonised."

Meanwhile, the Royal Institute of Chartered Surveyors has predicted the cost of the £50 billion scheme could end up rising significantly. However, with the project including a contingency margin of £14.4 billion, it is thought any rise in price could be contained within this allowance.