The four main parties to negotiations on an intellectual property waiver for Covid-19 vaccines have prepared an "outcome document" for approval by the broader membership, the World Trade Organization (WTO) said on Tuesday, with its chief hoping for a final deal by June.

WTO director-general Ngozi Okonjo-Iweala, who has made vaccine equity her top priority since taking office in 2021, has been working for months to broker a compromise between the United States, the European Union, India and South Africa to break an 18-month-long impasse.