Nepalese Prime Minister Girija Prasad Koirala was rushed to a hospital overnight after complaining of chest pain.
The 84-year-old prime minister is being treated at a hospital in the capital, Kathmandu. Officials say his condition is stable.
Mr. Koirala was scheduled to deliver the government's annual policy statement to parliament Tuesday, but doctors and government spokesmen say he will not be able to attend the session.
The prime minister was treated for prostate problems last month at a hospital in Bangkok.
Mr. Koirala became prime minister in April, after weeks of pro-democracy protests forced King Gyanendra to give up absolute power and reinstate parliament.