Prime Minister Lee Hsien Loong said he has no doubt Dr Tony Tan, if elected as President, will be a unifying figure for all citizens, and will bring honour and credit to Singapore.
PM Lee said that Dr Tan informed him he would be resigning from the Government of Singapore Investment Corporation (GIC) to contest the election as an independent candidate.
PM Lee is chairman for the GIC while Dr Tan is its deputy chairman and executive director. The 71-year-old is set to step down on 1 July.
He was making his first comments on the presidential polls in an email response to questions by the mainstream media.
PM Lee also made it clear that Dr Tan did not need his go ahead to enter the contest. "He did not need my permission, nor did he ask for it," the Prime Minister was quoted as saying by The Sunday Times (ST).
The former deputy prime minister, who retired from politics in 2006, said he did not have, or seek, the backing of any political party, and entered the race on his own accord.
PM Lee, in his email, also did not explicitly endorse Dr Tan as the government's preferred choice even as he spoke positively of Dr Tan.
He said, "I have known and worked with Dr Tan for more than 25 years. He enjoys high standing among Singaporean. I have no doubt whatsoever that if elected President, Dr Tan will be a unifying figure for all citizens, and will bring honour and credit to Singapore."
He noted, the President is a key person in Singapore's system of government.
"As the Head of State, he represents the country and all Singaporeans. He also has important constitutional functions, especially through his custodial powers over reserves and key appointments," outlined PM Lee.
"He must carry himself with dignity, and discharge his duties with judgment and integrity," he continued.
In the only previous contested election in 1993, government leaders backed former deputy prime minister Ong Teng Cheong, who came up against former accountant-general Chua Kim Yeow. This came a week before Nomination Day.
The 1999 and 2995 elections were uncontested with President S R Nathan as the government's endorsed candidate.
President Nathan is set to give his decision on whether he will contest this year's election in two weeks.
Tan Kin Lian said on Saturday he would be open to discussions with Dr Tan Cheng Bock about the possibility of either one stepping aside should both get the certificate of eligibility.
But he prefers to run, he told ST.
Dr Tan said he would not comment until Tan approached him.
The Presidential Election must be held by 31 August.