GENEVA (REUTERS) - The World Trade Organisation is being slowly strangled to death, a retiring trade judge whose replacement has been blocked by the United States said in his farewell speech, delivering a thinly-veiled rebuke to the Donald Trump administration.

Ricardo Ramirez-Hernandez served two terms as a judge on the WTO's Appellate Body, which acts as the final court for trade disputes between countries. Since his departure last year, the United States has been blocking the process to replace him and other judges, throwing the WTO into crisis.

"This institution does not deserve to die through asphyxiation," Ramirez-Hernandez said. "You have an obligation to decide whether you want to kill it or keep it alive." In a speech introducing Ramirez-Hernandez, WTO Deputy Director-General Karl Brauner said there was "no movement in sight" to unblocking appointments.

"This is frightening," he said, adding that it was an illusion to believe the WTO could manage without its appeals judges. It remained to be seen if the WTO was an achievement of civilisation or only a temporary experiment, he added.

The Geneva-based World Trade Organisation, founded in 1995, is the final arbiter for trade disputes between its 164 member economies and the main global forum for discussing trade.

Its appellate body normally has seven members, but because of the Trump administration's veto on new hires, only four of the posts are now filled. One judge is due for reappointment in September and two are due to leave next year.

Three judges are needed to hear any case, which means the court will cease to function altogether next year unless Trump lifts his refusal to fill vacancies.

Trump and his trade advisers take a tough and unorthodox line on what they see as "unfair" treatment by the trade body.

Ramirez-Hernandez did not point fingers directly at any particular country for the crisis, saying all WTO members were responsible for dealing with problems.

"It seems to me that the crisis we now face could have been avoided if it had been addressed face-on, as it began to escalate," he said.