Sussex commuters are bearing the brunt of some of the worst train delays in the country.

Rail operator Connex has come bottom of a survey by the Shadow Strategic Rail Authority comparing train punctuality between April and June last year and this year.

The all-day punctuality figures for Connex South Central were five per cent worse than last year, with only 87.6 per cent of trains arriving on time compared with 92.7 per cent in 1999.

For trains in the peak period the figure worsened by six per cent, with just 87 per cent of trains arriving on time compared with 93.4 per cent the previous year.

The figures were based on trains arriving within five minutes of their timetable time.

The French firm, currently bidding to renew its franchise for another 20 years, blamed its poor performance on ageing trains and infrastructure, a busy network and a shortage of drivers.

David Ewart, media relations manager for Connex, said: "Track circuit and points failures continue to play a significant part in adversely affecting train service delivery.

"Railtrack southern zone is working actively on the root cause of these failures and its impact.

"An increase in the number of infrastructure failures on the Brighton main line has seriously affected delivery of the train service compared to the same period last year.

"Temporary changes to the published timetable because of a shortfall in driver resources from staff leaving the service and joining other train operating companies has also had an impact. However, we have recruited in excess of 100 drivers in the last 12 months to help tackle this.

"Train failures and damage from vandalism have also made a significant impact on performance during the period in question.

"Connex operates the most intensively used service in the country and the system is very complex. Therefore any delays through signal failures very quickly impact on the system.

"We are working to improve our performance, but it has to be taken into account there has been a 25 per cent increase in the number of passengers using our service in the last four years. While we welcome this we have to cope with it using ageing trains running on a Victorian infrastructure.

"If we secure the new franchise we will renew all the slam door trains by 2002 and this will also improve punctuality."

Mike Hewitson, secretary to the Railusers Consultative Committee for Southern England, said: "Sadly, this does not come as a great surprise to us. We have had so many letters from customers complaining about punctuality.

"It is the number one issue year after year.

"Connex is still suffering the knock on effect of not having enough drivers to run its trains.

"But while it is not all Connex's fault we do expect to see performance improve year on year, not get worse.

"There needs to be continued efforts to make the whole package work and this has to be done now, rather than waiting for the new 20-year franchise."