Passengers using London Bridge are still facing disruptions and delays despite the introduction of a new timetable in mid-May.

The pressure on the grid is so great that any impact has a huge knock-on effect – in the last few days a signal failure at New Cross and a fallen tree at Forest Hill have caused cancellations and delays.

London Assembly member Caroline Pidgeon called rail bosses to account on June 9 for continuing failures.

The Assembly is investigating whether TfL should take on more suburban route franchises but she took the opportunity to press Phil Hufton, Network Rail’s managing director of networks operations, and Southeastern Railway MD David Statham on the impact of the multi-billion-pound London Bridge upgrade.

She told them: “My experience is that most of my trains are still not arriving on time or departing on time. You bought in a new timetable mid-May which has cut out even more services yet if I am on Southern travelling at peak 78% are on time, but on Southeastern its only 42%.

“Passengers have fewer delays but still an awful lot. Apart from the people in the pink tabards there’s not a lot that you will see directly yet you’re still experiencing a lot of delay. You’ve cut out more trains so you’ve got people cramming on to packed carriages.”

Lib Dem London Assembly leader Caroline Pidgeon

Mr Hufton apologised for any disruption. He said: “We still have a lot to do. We recognise some of the challenges we face. Over Christmas we thought we could have continued or increased trains per hour and we didn’t get it right.”

He outlined how he had turned London Bridge into a “military-style operation” seconding a senior British Transport Police officer for six months to handle “incident management” as well as working closer with train operators and improving communication with customers.

But he said “until perhaps January next year we’re going to have challenges”.

Mr Statham said that overall Southeastern was carrying 40% more passengers than 2006.

• Also online: Apple Pay comes to TfL

He said: “We decided the most appropriate approach was to reduce the number of trains per hour to try to reduce the problem. That has worked to a degree but we’re still not where we need to be. We still have a lot to do.

“We worked hard to plan for these works. We worked on the timetable, the communications, on the infrastructure.

“We’ve seen a 2% rise in our public performance measure since we introduced the timetable in January. That doesn’t sound a lot but those performance gains have been delivered in the light of some significant challenges around the rebuilding work.

“Since January we’ve lost the use of the two busiest pairs of platforms in Europe and we’ve lost half of the approach lines to London Bridge and the challenge for us is to drive up levels of performance during this massive capacity upgrade programme.”