British and Dutch rail officials remain locked in a row over one of Britain’s biggest train networks, with a controversial clause at the heart of the spat hitting its finances.

Abellio, a subsidiary of state-owned Nederlandse Spoorwegen (NS), wants to renegotiate what it calls a “flawed mechanism” in its franchise agreement for Greater Anglia.

The dispute has been overshadowed in recent weeks by the Scottish government’s decision to strip Abellio of the ScotRail franchise last month.

Pre-tax profit for Greater Anglia plunged more than 70pc to £1.7m, despite sales rising 8pc to £701m, according to recently filed accounts. Dutch officials last year threatened to take legal action over a clause that links payments from Abellio to the Department for Transport (DfT) to London employment figures.

A similar mechanism has also crippled the finances of strike-ridden franchise South Western Railway and is being disputed by operators FirstGroup and MTR.