SINGAPORE - Even as the Bukit Panjang LRT (BPLRT) undergoes an extensive multi-year overhaul, Minister for Transport Khaw Boon Wan has suggested service on the light rail line could be suspended during "certain off-peak hours" to reduce the stress on it.

Speaking at an event celebrating improvements in rail reliability at SBS Transit's Sengkang Depot, Mr Khaw said he had encouraged operator SMRT to consider the option, as the "risk of failure" is high for the ageing line.

"When (ridership) is very low on the BPLRT, you can serve the same demand quite adequately with buses," he said, adding this would help ease the load on the line with no loss of service to commuters.

The Land Transport Authority (LTA) later told reporters that SMRT is reviewing the "operational details" of the line.

In 2016, SMRT Trains managing director Lee Ling Wee had said on the transport operator's blog that scrapping the 20-year-old BPLRT and replacing it with buses was a possibility as part of a review of the disruption-plagued line, though the LTA later said that this was not practical.

Mr Khaw himself had said in Parliament in May last year that completely replacing the LRT with buses was not feasible as the road network in Bukit Panjang would not be able to cope.

In March last year, LTA signed a $344.25 million contract with supplier Bombardier for an overhaul of the BPLRT that includes replacing the signalling system and 19 trains and is expected to be completed by 2024.

The light rail line has been plagued by disruptions since it began service in 1999. In January last year, service was disrupted for almost five hours after a train damaged a piece of trackside equipment.

Figures from the Land Transport Authority show the BPLRT currently clocks some 66,000 km between delays of more than five minutes.

In comparison, the SBS Transit-operated Sengkang-Punggol LRT line hits 353,000km between such delays.