"She stood resolutely beside her husband, (the late) Tun (Abdul) Razak (Hussein), when he led Malaysia at a critical period in its history," said Lee in his latest update on his Facebook today.
"She will be remembered for her devotion to country and family," he wrote further in his posting in which he appended a photo of Rahah.
Rahah, 87, the widow of Malaysia's second prime minister Abdul Razak, died at the Prince Court Medical Centre here yesterday afternoon.
Rahah will be buried beside the grave of her sister Tun Suhailah Mohamed Noah, the mother of Foreign Minister Datuk Seri Hishammuddin Tun Hussein, at Masjid Negara's Heroes Mausoleum.
In the beginning of the posting, Lee wrote that he was "deeply saddened" to hear of the passing of Rahah, who is also the mother of former Prime Minister Datuk Seri Najib Tun Razak.
"Our thoughts are with her family and the people of Malaysia during this time of mourning," wrote Lee before ending the posting with his initials LHL.
-- BERNAMA