SINGAPORE - Train operator SMRT has acknowledged that it should have sought the approval of the Land Transport Authority (LTA) before allowing Anglo-Chinese School (Independent) to charter trains.

SMRT has also explained to LTA why they went ahead without getting prior approval, an LTA spokesman said on Wednesday.

Explaining why SMRT had to seek permission, the spokesman told The Straits Times: "This is because as a regulator, LTA is responsible for ensuring that train services to the public are provided as scheduled, and that any additional trips in the network do not adversely affect such services."

SMRT did not respond to queries.

LTA had said on Tuesday that SMRT could face possible sanctions for allowing the use of its trains for private purposes. It had allowed ACS (I) to charter five MRT trains on Tuesday to ferry its students, staff and alumni to the Schools National C Division rugby final at the new National Stadium.

Some netizens slammed the decision to allow public transport to be used for private purposes, while others felt that as long as most commuters were not affected, it was not an issue.

Defending its decision, SMRT had said earlier that chartered trains run between normal train services and strictly within off-peak hours. It also added that it had previously worked with schools to charter trains and transport students for large-scale events such as National Day Parade rehearsals.