Prime Minister Lee Hsien Loong has refuted the grave allegations of abuse of power levelled against him, and given his first detailed account of the saga of 38, Oxley Road.

Addressing a packed Parliament House, he disclosed how his father, Mr Lee Kuan Yew, had signed off on plans to redevelop his house before he died, which would save the historical parts of it even as it sought to keep some areas out of public view.

This showed that while he had wished that the house be demolished, he was prepared to consider other options, if the Government decided otherwise.

This, PM Lee said, was the main difference he had with his siblings, who believed Mr Lee was adamant that the house be torn down, with no room for compromise.

He added that Mr Lee had upheld the rule of law in Singapore throughout his life and would have expected the Government to apply the same standards of good governance even to him and his wishes for his house.

Admitting the allegations made by his siblings had damaged the country's reputation, he again apologised to Singaporeans, and explained his decision to bring the issue to Parliament for a full airing.

He said: "As the PM I have a duty to explain myself to MPs, and to rebut in Parliament the allegations against me and my government."

His account was supplemented by Deputy Prime Minister Teo Chee Hean's account of the ministerial committee on the house that he set up and which he chairs, that has also come under attack from Mr Lee Hsien Yang and Dr Lee Wei Ling. He told MPs that PM Lee had recused himself from decisions related to the Oxley house and left these to him and his colleagues.

National Development Minister Lawrence Wong then described the difficult spot the National Heritage Board had been put in by the two executors of Mr Lee Kuan Yew's will over their Deed of Gift for items from the house.

But PM Lee's reluctance to take his siblings to court drew a sharp response from Workers' Party (WP) chief Low Thia Khiang, who called for a swift end to the saga.

Mr Low said the siblings should not make vague accusations against the PM based on scattered evidence even as he chided ministers for engaging in a "Facebook brawl".

"Making allegations that appear to be calculated to undermine the Prime Minister's authority does not make for constructive politics in Singapore. It is a reckless thing to do and I do not see how this is in the national interest," he said.

Over seven hours, MPs discussed various options to resolve the issue - including having the key players appear before a special select committee - while PM Lee listened intently, flanked by his Cabinet colleagues. The 11 People's Action Party (PAP) backbenchers, five WP MPs and five Nominated MPs who spoke asked probing questions of PM Lee and his ministers.

Many said residents were puzzled as to why a family quarrel had become a national issue in recent weeks, played out on social media.

In his speech, PM Lee asked MPs to question him and his ministers vigorously and without restraint - so that doubts can be dispelled, and Singaporeans' confidence in their nation's institutions and system of government strengthened.

"We have nothing to hide," PM Lee said, noting that he had lifted the PAP Whip to signal his commitment to a robust airing of the issues.

He said he would also issue his remarks in the debate outside Parliament separately. This will exempt him from parliamentary privilege, which precludes him from being sued over remarks in the House.

His brother Lee Hsien Yang had cited this privilege to doubt PM Lee would give a truthful account.

PM Lee's siblings have accused him of abusing his power to set up a ministerial committee to block the demolition of their father's house, to further his personal ambitions.

Yesterday, PM Lee told Parliament that moving to knock the house down without going through due process "just because it was what my father wanted" would have been a real abuse of power.

"That would have abused my position as PM and gone against the whole system of rules and values that Mr Lee Kuan Yew built up.

"In Singapore, everyone is equal before the law. Mr Lee understood this most of all," he said.

In an hour-long speech, PM Lee set out before a full chamber the nature of family discussions on 38, Oxley Road. He disclosed that while Mr Lee Kuan Yew had long wished for the house to be demolished, he also explored various permutations for the house with the family.

In 2012, he signed an application to the Urban Redevelopment Authority, which approved a proposal to remove the private living spaces and renovate the house.

PM Lee said he heard nothing to the contrary until after his father died on March 23, 2015, aged 91.

When Mr Lee Kuan Yew's will was read to the family in April 2015, Mr Lee Hsien Yang for the first time objected to the renovation plans their father had approved.

PM Lee said that as a son, he wanted to see his father's wishes carried out, adding that there was no need to rush into making decisions on what to do with the house.

He said there was no substance to the dispute over the house, as he had recused himself from all government decisions on it and sold it to Mr Lee Hsien Yang.

PM Lee also responded to his siblings' accusing him and his wife Ho Ching of nepotism, of having political ambitions for their son Hongyi, and that PM Lee wanted the house to bolster his power. PM Lee said there was no basis for these claims.

"Regarding the house, and how its continued existence enhances my aura as PM, if I needed such magic properties to bolster my authority even after being your PM for 13 years, I must be in a pretty sad state," PM Lee said. "And if such magic can work, Singapore must be in an even sadder state," he added.

Yesterday, DPM Teo said the Government had a duty to consider public interest aspects of properties with historical and heritage significance. It was a point echoed by Mr Wong, who noted all properties with architectural or heritage merit were subject to due process.

The basement of 38, Oxley Road witnessed discussions leading to the formation of the PAP in 1954.

MPs who spoke touched on the issues of heritage and the need for due process. They said Singapore's reputation had come under international attention over this saga, and feared it was distracting the Government from more pressing tasks.

Mr Low said the matter should be taken to court, and others called for a select committee to be convened to resolve the issue, but Senior Minister of State Janil Puthucheary said neither would settle the feud soon.

PM Lee said fighting the matter out in court "cannot be my preferred choice". He believed he had a strong case, and the baseless allegations were a "very grave attack" on him and the Government.

But suing his own brother and sister would further besmirch their parents' names, drag the process out, and cause more distraction and distress to Singaporeans, he said.

This was why he hoped the Parliament debate would deal with the issue expeditiously and put it to rest.

"When the dust has settled on this unhappy episode, people must know that the Government operates transparently, impartially, and properly. That in Singapore, even Mr Lee (Kuan Yew)'s house and Mr Lee's wishes are subject to the rule of law," PM Lee said.

"That the Government he built is able to withstand intense and sustained attacks on its reputation and integrity, and emerge not just untainted, but in fact strengthened."

"This is the 'house' that Mr Lee built, not 38, Oxley Road," he said.

PM Lee will respond to the various questions raised by MPs when Parliament resumes today.