There were slight delays on the MRT rail network during Monday's morning rush hour as two separate trains on the East-West Line encountered train and door faults respectively, forcing trains in both directions to travel at reduced speeds.

SMRT advised passengers to expect delays of up to 15 minutes. SMRT said on its Twitter page that both faults were rectified by about 9am, but station platforms remained congested.

One eastbound train travelling from Pioneer to Queenstown station had suffered a door fault, while a westbound train had an unspecified train fault. In a separate incident, another train at Kallang station was temporarily delayed when the emergency button was activated for a passenger who felt unwell.

The latest delays come after last Monday and Tuesday's train and track faults caused 20- to 50-minute delays on the North-South Line. Commuters have faced a spate of delays on MRT trains since the new year. The Land Transport Authority had earlier said it would investigate last Monday's incident, which came a week after tougher penalties against serious train disruptions came into effect.

Under the new laws, operators can be fined up to 10 per cent of the annual fare revenue of an affected line, or $1 million, whichever is heftier. The previous cap was at $1 million per incident.