Lee, 90, Singapore's first prime minister, is currently on antibiotics and is recovering, local media reported today.
He has been in Singapore General Hospital since Sunday.
Lee, who served as 'Minister Mentor' after stepping down as prime minister in 1990, has been advised by doctors to avoid public appearances, his press secretary said in a statement.
He will not attend his traditional Chinese Lunar New Year Dinner in his constituency of Tanjong Pagar later this evening.
Currently, a Member of Parliament for Tanjong Pagar, Lee had traditionally made keynote speeches during the traditional dinner over the years.
But he missed the event last year for the first time due to health reasons. He wished all Singaporeans a Happy Chinese New Year.
Lee oversaw the separation of Singapore from Malaysia in 1965 and its subsequent transformation from a relatively underdeveloped colonial outpost with no natural resources into a developed "First World" city-state.
Today, he is recognised as an iconic global statesman and one of the most influential political figures in Asia.