London – The situation within the Sukarno family is deteriorating with a clear split between the sisters widening and "becoming more serious now", political analyst Hermawan Sulistyo has said.

He told the BBC's East Asia Today programme that more critical segments of Indonesian society had tried to get Ms Rachmawati Sukarnoputri "into their camps" against her sister, Vice-President Megawati Sukarnoputri. Mr Hermawan said on the programme on Monday that "to some degree, they"ve succeeded".

Explaining the reasons for what he saw as the estrangement between the two sisters, he said: "In the eyes of Rachmawati, Megawati is only the biological daughter of her father, while she is the real ideological daughter."

He said the country's founding President Sukarno often took a young Ms Rachmawati to political meetings and events, and trained her in politics. "So the President wanted Rachmawati rather than Megawati to be the politician," he said.

The rift between the two has been apparent ever since Ms Rachmawati refused to be involved in Ms Megawati's Indonesian Democratic Party-Struggle (PDI-P). It came under the media spotlight recently during a rally in East Java marking the 100th anniversary of Mr Sukarno's birth. There, in front of Ms Megawati, President Abdurrahman Wahid, top political leaders and thousands of people, Ms Rachmawati launched what was seen as a stinging atack on her older sister.

She warned that vital issues such as nation-building were being ignored while the country's Parliament had launched what she described as a coup d'etat – a reference to the efforts to remove Mr Abdurrahman as President.

The BBC said that in recent months, Mr Abdurrahman had tried to woo Ms Rachmawati to his side in an effort to sow doubts and create divisions within the PDI-P over the planned impeachment of the President next month.