Philippine authorities Tuesday banned most organ transplants to foreigners and vowed tough punishments for lawbreakers to stem a thriving trade in poor Filipinos selling their own kidneys.

Health Secretary Francisco Duque said a moratorium on such transplants was already in effect and that within two weeks, sanctions would be laid against institutions that perform any surgery, as well as recipients and middlemen who broker the traffic.

Foreigners who receive transplants from non-related living Filipino donors and the middlemen could face up to 20 years in jail and a fine of as much as two million pesos (47,400 dollars), Duque told a news conference.

Duque said the crackdown was part of the "ethical and moral imperative to protect Filipinos, especially the poor," who may be induced into selling their organs for money.

He said kidney transplants from Filipinos to foreigners had increased by 62 percent between 2002 and 2006.

Of about 620 kidney transplants carried out in the Philippines in 2006, 63 percent involved foreign recipients, mainly from the Middle East and Europe, Duque said.

This violated an earlier health ministry rule that Filipino hospitals that carry out kidney transplants should limit foreigners to only about 10 percent of their recipients.

Of the 24 hospitals authorised to perform kidney transplants, 14 were found to have exceeded that limit and could face sanctions, the department said.

Duque said that eventually, the government would seek to expand this to a ban on non-related living Filipinos donating kidneys to other Filipinos.