For Prime Minister Najib Abdul Razak, the opposition’s alternative budget – which includes pledges to scrap the goods and services tax (GST) and increase oil royalties – is little more than "populist".

“The opposition budget is not based on facts and figures, and will create a big hole in government finances,” he said, as quoted by Bernama.

Najib said the opposition’s lack of cohesive leadership is reflected in its budget proposals, which “lacked credibility and consistency”.

“It shows that their measures are purely populist but cannot be backed by substance, such as revenue. The measures are not doable so, therefore not sustainable,” said Najib in a briefing with media editors in Putrajaya today.

Pakatan Harapan's alternative budget, which was unveiled yesterday, promises to scrap the GST and revert to the sales and services tax (SST) within a year of winning the election.

It will also offer 20 percent royalties to the oil-producing states of Kelantan, Terengganu, Sabah and Sarawak.

Despite his criticisms, however, Najib said providing the opposition with a fair share of the 2018 Budget was a “moral duty.”

“Some things, for example, the water supply, are the moral duty of the federal government.

“We cannot deprive the people from getting clean water just because we don’t rule their states. Even some of the highways run through opposition-controlled states.

“We want to show that we are responsible, and there are times we have to rise above politics. We have to fulfil our moral obligation as a government,” he said.

On Budget 2018, which is to be announced tomorrow, Najib said the biggest challenge was fulfilling the people’s expectations.

The prime minister said his budget team have toiled hard to prepare the budget, adding that he expected Malaysians to understand that any sustainable budget must reflect sound economic management.

He also noted that “whatever is said or done” in relation to the budget, there are those who will invariably perceive it as an election budget.

Although admitting that it is easy to label it as such, Najib maintained that the government has been consistent in introducing projects to benefit the people.

The 2018 Budget will be tabled in Parliament tomorrow, the first to be announced at the earlier time slot of 3.30pm.

“It starts at 3.30pm for the first time because Maghrib is at 7pm. We want to make sure that there is time for Asar prayers and it won’t prolong into Maghrib. We cannot change the time of Maghrib but the budget time can be changed.”

The prime minister promised to keep his speech short but noted that he has a lot to say.