Train operator SMRT's incoming chief executive officer Neo Kian Hong joined Transport Minister Khaw Boon Wan yesterday in visiting staff during the first full-day trial of the new signalling system.

The trial on the East-West Line during operating hours will take place on five Sundays until May 27.

The new communications-based train control system will allow trains to run closer together, and arrive at intervals of up to 100 seconds during peak hours, instead of 120 seconds currently.

During the visit by Mr Khaw and Mr Neo, teams from the Land Transport Authority and SMRT were also present to gather feedback on ground operational matters, said SMRT in a Facebook post yesterday.

SMRT also added in its Facebook post that while it it is "optimistic that the process will be smoother than the North-South Line testing", there may be "minor glitches and delays" during the Sunday trials.

Previously, tests of the new signalling system were done outside train operating hours.

All 35 stations along the East-West Line have had their operating hours on weekends shortened since March 2, so as to provide more time for engineering staff to intensify testing of the new signalling system.

During the full-day tests, the East-West Line will connect the Gul Circle and Joo Koon stations.

After a train collision at Joo Koon station on Nov 15 last year, the section of the line was disconnected.

According to a previous Straits Times report, by the end of next month, if all goes well, week-long live testing will begin. The system is expected to be fully ready by June.

SMRT announced on April 18 that Mr Neo, a former general and permanent secretary, will succeed incumbent chief executive Desmond Kuek from Aug 1.