92-year-old Dr Mahathir made history earlier this month by defeating the incumbent at the polls and ushering in Malaysia's first transition of power since independence, at the watershed 2018 Malaysian General Election.
Prime Minister Tun Dr Mahathir Mohamad said the crowdfund, dubbed Malaysia's Hope Fund (Tabung Harapan Malaysia), was formed following concern from fellow Malaysians over the economic mismanagement by the former Barisan Nasional government.
Abdul Rahman said that it was "too simplistic" for the Prime Minister to say that the project "won't be beneficial because it's going to cost the country a huge sum of money and it will make no money at all from the operation".
The project, valued by analysts at about US$17 billion, was out for tender and was expected to be completed by 2026.
The Straits Time said planning work had already began on Singapore's end.
On May 12, the Malaysian government's delivery vehicle for the high-speed project, MyHSR, released a statement congratulating Mahathir Mohamad on being sworn in as the country's seventh prime minister.
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A lack of capacity in pipelines or in rail cars to ship oil produced in Alberta is also hurting Canada's energy sector. Construction costs going forward will be included in the $4.5-billion sale price if no buyer is found.
"I think the people of Singapore, like the people in Malaysia, must be exhausted of having the same government, the same party since independence", he said in an interview with the Financial Times.
The newly-elected government is looking to reduce its commitment to major projects in a bid to trim Malaysia's national debt.
Jurong Lake District is where the terminus for the high speed rail was to have been sited - into Singapore's second central business district.
Dr Walter Theseira, senior lecturer at the Singapore University of Social Sciences, said it would be a "great missed opportunity" for both countries if plans for the HSR were to fall through, as the project would have strengthened both Singapore's and Kuala Lumpur's positions as regional business hubs.
Rahman said Malaysia would lose an estimated RM209 billion in gross national income (GNI) contribution and also the potential to create 70,000 jobs if the HSR was canceled.
The prime minister had earlier announced plans to revoke a controversial goods and services tax that was meant to rake in 43.8 billion ringgit (US$11.05 billion) this year, and reinstate fuel subsidies amid rising oil prices.