Aung San Suu Kyi was invited to visit Britain when she met Prime Minister David Cameron in Yangon on Friday.
At the time, she said the fact that she would consider the offer, rather than reject it outright, showed "great progress" had been achieved in Burma.
Suu Kyi, 66, was first detained in 1989, and spent 15 of the next 21 years in detention, refused to leave the country during the brief periods when she was not held by authorities, for fear of not being allowed to return.
Her long refusal to leave Burma characterised her steely determination to defy the ruling junta, which offered to release her from house arrest to be with her late husband, Michael Aris, who died of cancer in Britain in 1999.
More top news
Low pressure remaining in control gives more unsettled weather for the UK this weekend.
Charlie Gard, the baby boy whose fight for life captured the attention of the world has died, his family has confirmed.
A Royal Marine who lived a "dangerous double life" as a terrorist bomb-maker claims he faked Irish Republican sympathies out of fear.