Theresa May has defended rail fare increases by insisting investment is needed.

The Prime Minister said rises in regulated fares are kept to inflation, with 97p of every pound paid towards a ticket being put into the railways.

Fares rose by an average of 3.4% last week, with an annual pass from London to Brighton rising from £3,832.00 to £3,968.00 (3.5 per cent).

Hove MP Peter Kyle blamed the government for the "insulting" rise to prices.

Speaking to BBC1's Andrew Marr Show, Mrs May said: "Since privatisation, usage of the railways has doubled and we have seen the biggest investments since Victorian times in our railways.

"A lot of people rely on our railways, we want to see good service on our railways but that does mean that investment is needed."

Today, commuters will again be affected by strikes.

Conductors from the RMT Union will be taking industrial action today. Southern said that most services will operate normally.

In a statement on their website Southern said: "The full Gatwick Express and Thameslink service is expected to operate on all routes.

"It may be necessary for a queuing system to be put in place at Clapham Junction.

"South Western Railway services will also be affected."