A new telephone abortion service that allows women to terminate their pregnancy without meeting a doctor or pharmacist face-to-face has been so overwhelmed by prospective patients it cannot meet the demand, its medical director says.

On Monday, Fairfax Media revealed a service called the Tabbot Foundation would prescribe mifepristone and misoprostol (commonly known as RU486) for women who are suitable for a medical abortion and are assessed via telephone consultation.

The service has since received enquiries from four times the number of people it is able to treat, and is now trying to find alternative services for some women.

The World Health Organisation categorises mifepristone and misoprostol as "essential medicines" that all women should have access to, but in Australia it can be extremely difficult to obtain and costly.