The MTR Corporation on Tuesday said a new signalling system to increase train frequency will be introduced on the Tsuen Wan Line by 2025 at the earliest, and the system will gradually be extended to other lines by 2029.

The system's development suffered a major setback after two trains collided at Central Station during a drill in 2019.

Operations director Tony Lee said the contractor involved later put forward amendments to the software.

“When we reviewed our current plan, we found that its completion time is longer and its complexity is higher than what we had expected,” he said.

“The set-up of the amendment plan is standardised, and it has been running well for long in different parts of the world. On top of this standardised design, we will make it compatible with our special operating environment.”

“[The new plan] boosted the safety and reliability [of the signalling system], and it allowed us to have a better idea about its completion date.”

Meanwhile, the corporation said 93 new trains will gradually be brought into service to replace current trains that are some 40 years old. The first new train will start running on the Kwun Tong Line on November 27.

Jeny Yeung, transport services director, said the new eight-car trains have wider doorways that allow for smoother boarding and alighting, as well as more poles and straps for passengers to hold on to.