Lindsay Sandiford could seek a judicial review if Indonesia's Supreme Court rejects her latest death penalty appeal, human rights campaigners have said.
However, such a move would largely depend on whether new evidence had come to light, they added.
After that, her final resort would be to seek a reprieve granted by the country's president.
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Mr Ramaphosa, South Africa's deputy president, is likely to succeed current President Jacob Zuma when his term in office ends in 2019.
ITV News has uncovered claims that some anti-poaching rangers working in a UK aid-backed project were complicit in elephants' slaughter.