Reports from Samoa say the acting prime minister Papali'itele Niko Lee Hang is vowing to look into an apparent conspiracy to displace the prime minister.

Tuilaepa Sailele Malielegaoi has been in hospital in New Zealand and is due back in Samoa on Sunday.

Papali'itele told the Samoa Observer he had taken steps to get to the bottom of the conspiracy reports.

He said he had arranged a meeting with backbencher Faumuina Wayne Fong, who had raised the issue last week.

Faumuina had labelled the reported late night meetings "dirty politics".

Rumours of power jostling among Human Rights Protection Party members have been rife since Tuilaepa was airlifted to New Zealand within hours of being admitted to the High Dependency Unit of the National Hospital in Apia.

A former cabinet minister who has been an ally of Tuilaepa has been accused privately of orchestrating a late night meeting with several HRPP members, supposedly to hatch a plan to take over the premiership.

Our correspondent reports many in the know say this was the main reason a scheduled October sitting of Parliament has been deferred by the Head of State "until further notice".

Parliament has in the past continued to sit when past prime ministers have taken ill, including Tuilaepa.

The Acting Prime Minister Papali'itele told the Samoa Observer that he had heard speculation from other members of Parliament and he said he thought it was time they were exposed.

He intended to get the names during his meeting with Faumuina "and then I will get those names and report back to the Prime Minister", he said.

Samoa PM due home on Sunday

Tuila'epa was flown to New Zealand by air ambulance two weeks ago.

RNZ Pacific correspondent in Samoa, Autagavaia Tipi Autagavaia, said there had been little detail about the state of health of the long serving leader.

He said people have been kept in the dark since Tuila'epa was admitted to intensive care at Samoa's national hospital in Apia at the beginning of this month.

"Only statements from the government through the first secretary saying of the prime minister, there is nothing to worry about, the prime minister is doing well in New Zealand and he is sending his love and his best wishes to everyone here in Samoa."

"The latest that we have, the acting prime minister, Papaliitele Niko Lee Hang, who is the minister of works and infrastructure, telling the media here that the prime minister is looking forward to returning on Sunday," he said.