The London Stock Exchange computer crash brought trading in shares to a halt today despite the existence of new rivals.

Recent launches of alternative share trading platforms including Chi-X and Turquoise were intended to provide an alternative to the LSE stranglehold.

Analysts had warned that today's outage could cost the LSE dear as it comes as it faces no fewer than seven rivals.

But in the event, very little dealing was carried out through the new routes with dealers saying they still relied upon the primary LSE to get reliable prices, even if they carry out the trade over a rival trading system.

Turquoise chief executive Eli Lederman said there had been very little trading in London shares today on his platform, which opened seven days ago.

He said: "One benefit you would expect from decentralisation [away from the LSE] is that there will not any longer be this dependence on a single platform.

"In fact, you see today with this major extended outage that trading in the UK has ground to a halt. That is a measure of the importance the primary market still has."

However, he added that the LSE's dominance would gradually be worn away as brokers work out how to reliably use the new alternative systems: "We are not there yet, but it will happen."

Chi-X is also thought to have had very little volume today.

Its chief executive, Peter Randall, said, however: "It's a good thing that there is choice now in Europe and people can choose."