Australia's richest woman, Gina Rinehart, invited a small group of Coalition friends for drinks in her private hotel suite, after planning a secret flight to Canberra to visit the Agriculture Minister Barnaby Joyce.

Some of Mrs Rinehart's closest political friends, the Speaker Bronwyn Bishop and Liberal Party senators Cory Bernardi and Michaelia Cash, were invited to join the billionaire for the intimate gathering on Wednesday night.

Gina Rinehart at the maiden lower house speech of Agriculture Minister Barnaby Joyce on Thursday. Credit:Andrew Meares

The iron ore magnate, who has vigorously supported Prime Minister Tony Abbott's plans to abolish the carbon and mining taxes, suggested the politicians meet for drinks in her Canberra hotel room to avoid media attention.