The head of India's ruling Congress party, Sonia Gandhi, has returned home after undergoing surgery in the United States for an undisclosed illness.

A party spokesman said the 64-year-old returned home Thursday and was “fine” after spending about a month abroad recovering from surgery.

Party officials announced on August 4 that Gandhi had undergone a successful operation in the United States, although they declined to give any other information about her condition.

Gandhi appointed a four-member group to run the political party in her absence. The group included her son Rahul, who is widely seen as a future prime minister.

Born in Italy, Gandhi is the leading figure of a family that has ruled India for most of the period since it won independence from Britain.

She is the widow of assassinated former Prime Minister Rajiv Gandhi. Her mother-in-law, Indira Gandhi, was also assassinated

while serving as prime minister, in 1984. And Indira Gandhi's father, Jawaharlal Nehru, was India's first premier.

The Nehru-Gandhi dynasty is not related to independence leader Mahatma Gandhi.