"He was a strong opponent of monuments, particularly of himself", they said.
"I deny these allegations", wrote the prime minister on Facebook.
The prime minister said he would address the issue more fully on his return.
"We are concerned that the system has few checks and balances to prevent the abuse of government". Lee Wei Ling, said in a statement "we feel big brother omnipresent".
Mr Tan said that the committee has made clear to Dr Lee Wei Ling and Mr Lee Hsien Yang that the government has no intention of doing anything with the house as long as Dr Lee continues to reside there.
Lee Hsien Yang meanwhile told the Financial Times newspaper he had not decided where to move to.
The siblings contend Lee Hsien Loong has sought to establish a dynasty-like rule over Singapore following the passing of their father Lee Kuan Yew-Singapore's revered former leader, responsible for its astonishing economic advancement and deeply mourned upon his death in 2015.
Prime Minister's brother Lee Hsien Yang said in a Facebook statement that he was leaving Singapore, citing the Hsien Loong as the sole reason for his departure.
Wei Ling and Hsien Yang stated the following: "We have seen a completely different face to our brother Hsien Loong, one that deeply troubles us".
According to the statement, throughout his entire life, Kuan Yew's sole focus was on Singapore and its future.
The situation is such that Hsien Yang feels compelled to leave Singapore. It is heart wrenching for me to leave this country. This is the country that my father, Lee Kuan Yew, loved and built. The late premier had said he wanted his home demolished after his death. I have no desire to leave.
His siblings have attributed this refusal to Hsien Loong's political ambition.
Hsien Loong denies claims made by siblings
They gave no specific details to back up any of their allegations. He passed away in March 2015.
"Ultimately, how much damage to the Lee brand is done is another question", he added.
"Since Lee Kuan Yew's death, there have been changes in Singapore that do not reflect what he stood for", the younger Lees said in their statement. "He was authentic and spoke his mind", the younger brother and sister said.
He also said the committee has been looking at how the late Mr Lee's will came to be made and the roles played in this by Mrs Lee Suet Fern - Mr Lee Hsien Yang's wife - and the law firm that she heads. The two younger children are the joint executors of his Lee Kuan Yew's will in which he states his wish to see his home demolished upon his passing.
Wednesday's statement did not explicitly state any dangers posed to siblings but said that the PM was driven by a desire for "power and personal popularity", milking his father's legacy for political purposes.
The feuding comes nearly a year after Lee Wei Ling took to Facebook in April last year to accuse her brother of abusing his power and forming a political dynasty.
In her Facebook post on Thursday, Dr Lee said she is in Scotland on holiday. "We also believe, based on our interactions, that they harbor political ambitions for their son, Li Hongyi".
Nick Foley, president, SEA and Japan, Landor Associates added that there is "nothing particularly remarkable" about the comments made by the Prime Minister's siblings.
Mr Tan said the committee had also invited Dr Lee and Mr Lee Hsien Yang to put their response by way of a statutory declaration, as PM Lee had done.
Rather, she alleged that PM Lee's "misuse (of) his official power" against his siblings in relation to the house at 38, Oxley Road suggests he could do the same to ordinary citizens.
"Moreover, even if Hsien Loong did not live at 38 Oxley Road, the preservation of the house would enhance his political capital", they said.
Lee Kuan Yew. Photo: Kevin Lee via Flickr. Our father placed our country and his people first, not his personal popularity or private agendas. They added: "We feel hugely uncomfortable and closely monitored in our own country".
Ben Stiller & Vince Vaughn Need Your Help in Hilarious 'Dodgeball' Reunion Video
Stiller's foundation benefits children in Haiti by providing educational opportunities - such as, building more schools. It's amusing because once you do the makeup and get the wig on, then you're suddenly like, "Oh yeah, I got this".
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