Myanmar's former junta leader Than Shwe has endorsed his one-time nemesis Aung San Suu Kyi as a "future leader" of the country, according to his grandson.

Than Shwe, a postal clerk turned general who ran the country with an iron fist for nearly two decades, met with Suu Kyi on Friday.

Her party is preparing for power after November's election win.

The talks mark a dramatic turnaround in fortune for Suu Kyi, who was kept under house arrest for 15 years by the 82-year-old retired general for leading the democracy movement against his army.

"Everyone has to accept the truth that Daw Aung San Suu Kyi will be the future leader of Myanmar after winning the elections," Than Shwe was quoted as saying on a Facebook post late Saturday by his grandson, Nay Shwe Thway Aung.

Daw is a term of respect.

"I will support her earnestly as much as I can if she really works for the development of the country," he added, according to the post.

The former strongman's grandson said he acted as an intermediary for the talks.

Win Myint, a spokesman for Suu Kyi's National League for Democracy (NLD) party, confirmed the Friday meeting, adding it was the first time the pair had met since 2003.

Suu Kyi is barred from the presidency by an army-scripted constitution, but has said she will govern from "above the president" when her party take their seats in the new year.