YANGON (REUTERS) - Aung San Suu Kyi is positive about Myanmar's future after meeting the former dictator who detained her for 15 years, an aide said on Saturday following her latest overture to erstwhile enemies before a historic power shift.

Suu Kyi met secretly on Friday with the former strongman Than Shwe, a psychological warfare expert turned junta supremo, who faded from the public eye after transferring power to a reformist, quasi-civilian government in 2011.

The two were at odds for two decades as Suu Kyi led a non-violent struggle against the army rule under which Myanmar was a pariah and kleptocracy isolated by the West. Than Shwe kept Suu Kyi under house arrest for most of his 19 years in power.

Her National League for Democracy (NLD) won last month's general election, trouncing a ruling party formed by Than Shwe. That outcome was interpreted as both an NLD public mandate and a protest vote against the military's political role.

"Aung San Suu Kyi told us that U Than Shwe said to her he was in favour of democracy taking root in Myanmar and also recognised her activities and achievements," Win Htein, a senior NLD leader, told Reuters. U is a Burmese-language honorific.

"They talked about laying a solid foundation for democracy."

The meeting comes amid a flurry of peacemaking moves by the Nobel laureate towards the heavyweights of a junta that persecuted her movement and saw the former British colony crumble under trade embargoes and economic mismanagement.

Suu Kyi met Wednesday with Than Shwe's protege, Min Aung Hlaing, who heads a military the NLD must work with in a power-sharing government next year.

The junta wrote a constitution that enshrines roles for the military in the executive and legislative branches, widely seen as safeguards for the its vast business interests. Any NLD attempts to change that soon could face resistance.

Suu Kyi met Than Shwe due to "her belief in his influence on the government and the Tatmadaw (military)," Win Htein said.

That view is shared by many in Myanmar, who have long believed Than Shwe was either dead or still running the country from behind the scenes.

Neither Than Shwe nor his inner circle have publicly revealed why they chose to dissolve the world's longest running military regime and allow political and economic liberalisation.