Competition between rail and coach firms for passengers between Birmingham and London has intensified, with Avanti West Coast cutting its cheapest fare by a quarter to £9.

The move – which applies to heavily restricted “Superfare” tickets – is intended to lure travellers away from slower rail and road options on the 113-mile journey between the two cities.

Sarah Copley, commercial director for Avanti West Coast, said: “We’re working hard to encourage more people to take the train and the new Superfare ticket on the Birmingham route, at just £9 for over 100 miles, is great value for money.”

Passengers must book between between one and three weeks in advance for a morning, afternoon or evening departure, and are told only 24 hours ahead which train they are on.

Two other rail firms, London Northwestern Railway (LNR) and Chiltern, offer Advance tickets that can be bought for specific trains.

LNR runs from Birmingham New Street to London Euston in direct competition with Avanti West Coast, while Chiltern operates from the city-centre station of Birmingham Moor Street to London Marylebone.

Research by The Independent, looking two weeks ahead, found the following Advance tickets available from Birmingham to London on Monday 20 October:

Advance fares are discountable with a railcard, reducing each fare by 34 per cent.

The Avanti West Coast price could be cut to £9 using the Superfare deal, but the passenger cannot specify a particular train.

With the main rail unions, Aslef and the RMT, involved in long and bitter disputes with train operators, it is not advisable to book more than two weeks ahead in case another strike is called.

Three intercity coach operators are also involved in a fares war between Birmingham and London.

For travel from Birmingham City Centre to Victoria Coach Station in central London, booking two weeks ahead, Megabus has a range of departures at £5.41 – plus a £1 booking fee that covers multiple passengers and journeys if required.

FlixBus has most departures priced at £6.99, plus a £1 service fee.

The National Express fare is £10.90 on most departures two weeks from now. A booking fee of £1.50 applies.

The coach journey takes about three-and-a-half hours, more than twice as long as the fastest train.