Mr Lee Kuan Yew's condition remains "largely unchanged" since the previous update issued on Mar 6, the Prime Minister's Office said in a statement on Friday (Mar 13).
In a Facebook post on Friday morning, Prime Minister Lee Hsien Loong - Mr Lee Kuan Yew's son - said that his family was "deeply touched" by the support shown by well-wishers.
"In the month since Mr Lee Kuan Yew was admitted to hospital, so many people and groups have sent him good wishes. On behalf of my father, I thank you all. My family and I are deeply touched by your encouragement, support and prayers," said the Prime Minister.
He added among those to send get-well cards and messages were residents and grassroots leaders of his father's Tanjong Pagar GRC and other constituencies), students from PCF Sparkletots preschool and other schools, and Ain Society - "as well as many others whose lives he touched, or who are grateful for what he has done for Singapore".
The cards have been arranged in Mr Lee Kuan Yew's office "to welcome him back when he's better", said the Prime Minister.
Mr Lee Kuan Yew, Singapore's first Prime Minister, has been in hospital since Feb 5, when he was admitted for severe pneumonia.
In a Feb 28 statement, the PMO said: "He remains sedated and on mechanical ventilation in the ICU at Singapore General Hospital. He is continuing with his antibiotics." In another statement issued on Mar 6, the PMO said that his condition remained "largely unchanged", with doctors continuing to monitor his condition.