The deteriorating health condition of Singapore's former leader Lee Kuan Yew has caught global media attention amid concerns over the country's political prospects.

Lee, Singapore's founding father and former prime minister, remains "critically ill" and his condition has deteriorated further in hospital from severe pneumonia for nearly six weeks, Singapore's Office of the Prime Minister said on Wednesday.

The update came after the office's previous notice on Tuesday, which said that Lee's condition had worsened due to an infection and that he has been on antibiotics.

Lee, 91, has been hospitalized since February 5.

Since 2009, Mr. Lee has been fighting a neurological disease that makes it difficult for him to walk, his daughter Lee Wei Ling, a neuroscientist, wrote in Singapore's Sunday Times in 2011.

Despite having retired from politics, the legendary leader's health has been watched closely for his continuing influence over Singaporean politics.

Deng Yuwen, a commentator on Singapore affairs, believes Lee's health may affect the current administration.

"Lee Kuan Yew, as Singapore's founding father, commands a strong influence over the government. But his son Lee Hsien Loong's influence is not as strong as his father's," Deng told the Global Times, adding that there has already been some opposition against the current government.

Lee Hsien Loong took office as Singapore prime minister in 2004.

He himself returned to work in early March after a successful surgery to treat prostate cancer.

In the last election in 2011, the ruling People's Action Party (PAP) won 93 percent of the seats despite a drop to around 60 percent in the popular vote. Many voters complained about high living costs and a rise in immigration.

Lee Kuan Yew, known as the engineer of the Singapore model, had a central role in building Singapore into one of the world's wealthiest nations on a per capita basis.

He co-founded the PAP, which has ruled Singapore since 1959, and led the newly born country when it was separated from Malaysia in 1965. Lee stepped down as prime minister in 1990.

Deng believes that relations between China and Singapore, which have been stable over the years, will not be shaken by Lee Kuan Yew's failing health.

Referred by former Chinese President Hu Jintao "an old friend of China," Lee visited China dozens of times, and has developed close economic exchanges with China amid its market reform.

Lee is also known for his knowledge of China's development and has been offering counsel to Western politicians on China's affairs.

China was Singapore's biggest trading partner in 2013, with bilateral trade worth $91.4 billion.