Founding Prime Minister Lee Kuan Yew has been given one of Japan's top honours for foreign leaders.
He will be posthumously conferred the Grand Cordon of the Order of the Paulownia Flowers, Japan's Chief Cabinet Secretary Yoshihide Suga said at a press conference on Tuesday.
"Mr Lee strived to strengthen relations with Japan and was successful in building a friendship between the two nations," Mr Suga told reporters after a Cabinet meeting.
The Japanese Embassy in Singapore announced on its website that the conferment of the award was backdated to March 23, 2015, the day Mr Lee died.
A spokesman for Singapore's Ministry of Foreign Affairs said it is deeply honoured and appreciates Japan's decision to confer the award on Mr Lee. He added: "This is in recognition of Mr Lee's contributions to the development of relations between Singapore and Japan over several decades."
Both nations share close ties, and celebrate their 50th anniversary of diplomatic relations this year.
Japanese Prime Minister Shinzo Abe attended the state funeral for Mr Lee, who died at age 91.
Mr Lee was given the Grand Cordon of the Order of the Rising Sun in 1967. Previous foreign recipients of the Grand Cordon of the Order of the Paulownia Flowers include former Indian prime minister Manmohan Singh and former US Secretary of State George Shultz.
Dr Lam Peng Er, a Japan expert at the National University of Singapore's East Asian Institute, said Mr Lee is seen as a "sage-like" figure in Japan and was often consulted for his honest critiques.
He said Singapore-Japan ties were "future-oriented" and added of Mr Lee: "He was the eldest statesman in Asia and welcomed Japan's economic, cultural and diplomatic presence in South-east Asia."
Dr Naoko Kumada, a research fellow at the S. Rajaratnam School of International Studies, said: "The Japanese learnt from his memoirs the tragedy that Mr Lee and the people in Singapore experienced during the Japanese Occupation and Mr Lee's determination never to forget that experience.
"Despite this, he took a practical and open approach towards Japan after he became prime minister. He built a positive relationship between Japan and Singapore by learning from Japan's success in industrialisation from the 1970s and built a strong economic partnership between the two countries that has become today's friendship."