A van driver, who was originally fined $10,000 for negligently causing the death of an elderly pedestrian, was given a two-week jail term instead yesterday, following an appeal by the prosecution to the High Court.

David Joseph John, 62, a market stallholder, was also banned from driving for five years for failing to keep a proper lookout while he was driving along Outram Road on the evening of Nov 13, 2015.

As he was approaching a corner with a side road, his van struck 79-year-old pedestrian Wong Fook Hin, who had already crossed three lanes of the five-lane road from the driver's left to right.

Mr Wong was taken to Singapore General Hospital with severe injuries. He never regained consciousness and died 10 days later.

In March, John pleaded guilty to a charge of causing Mr Wong's death by a negligent act. A second charge of causing grievous hurt to a nine-year-old cyclist in a separate traffic accident three weeks earlier, along Jalan Bukit Merah on the evening of Oct 23, was also taken into consideration during sentencing.

The district judge imposed the maximum $10,000 fine, saying that John's level of culpability did not merit a jail term. She placed weight on the fact that Mr Wong's act of jaywalking had a "direct bearing" on the driver's culpability and had a mitigating effect on the extent of his blameworthiness.

Yesterday, Deputy Public Prosecutor Christina Koh argued that the fine should be substituted with a jail term of between two and four weeks.

The DPP argued that the district judge had no cogent reason for departing from sentencing guidelines set in 2014 by a three-judge High Court panel, which ruled that the starting point in sentencing for a case of traffic fatality was up to four weeks' jail. DPP Koh argued that John's degree of negligence was not affected in any way by the fact that Mr Wong had been jaywalking.