Former US President Jimmy Carter has died, his foundation the Carter Center has announced.

Carter served as the 39th president from 1977 until 1981. He was aged 100, making him the longest-lived president in US history.

During his tenure as president Carter faced a spate of foreign policy challenges and the Democrat was defeated in his re-election bid by Ronald Reagan.

Last year it was announced that he would receive hospice care at home, following the end of his medical treatment.

Carter had been suffering health issues, including a melanoma that spread to his liver and brain.

In a post on social media, the Carter Center says: "Our founder, former US President Jimmy Carter, passed away this afternoon in Plains, Georgia."

Democrat Jimmy Carter, who was US president from 1977 to 1981, lived longer than any other president after leaving the White House.

His humanitarian efforts earned him the Nobel Peace Prize after his time in office.