Global travel agency STA Travel has stopped selling Royal Brunei Airlines flights in protest at the country's new death penalty for gay sex.

Full sharia law was enacted on Wednesday in the southeast Asian kingdom, prompting calls to the federal government to revoke Royal Brunei's right to land in Australia.

STA Travel says it will no longer work with Royal Brunei Airlines and has stopped selling the carrier's flights through its global operations.

"We categorically don't support laws that have recently been introduced in Brunei (including on Brunei-registered aircrafts and vessels) which we believe are in direct contravention of basic human rights," Australian manager Monika Rieker said.