World Trade Organisation (WTO) states appeared to edge closer towards a crucial deal on cheaper medicines for poor countries to help them face emergencies such as AIDS, malaria and tuberculosis.
But trade officials and envoys said key differences remained.
WTO countries have been wrestling for weeks with the problem of how to convert a political pledge on cheap drugs made by trade ministers into a practical programme to help some of the world's poorest countries deal with major health crises.
"We have had a good meeting," said Kenya's amabassador Amina Chawir Mohamed, who speaks for the African Group of countries at the 144-nation trade body. On the table was a proposed new draft drawn up by talks chairman ambassador Eduardo Perez Motta of Mexico with the aim of sealing a deal by Friday's deadline.
At the meeting on Monday, 17 of the 27 WTO members which spoke - amongst them the European Union, South Africa, Canada and India - said they could accept the new plan put forward by the Mexican envoy, trade officials said.
"Most countries said it was an improvement," one official said after the closed-door session.
But WTO decisions have to be taken by consensus and a number of countries, including the United States and the African Group, said they still had problems.
In launching the Doha Round of free trade talks in the Qatar capital 13 months ago, trade ministers agreed states should be able to set aside intellectual property laws, or patent rights, held mainly by pharmaceutical firms based in rich countries and order domestic companies to manufacture cheaper varieties.
But many developing countries, and particularly African states where AIDS is killing millions of people each year, do not have domestic drugs industries and would need to import the medicines.
But it has proved difficult to agree on details of how to carry out the idea, including what safeguards to include against abuse and what diseases should be covered.
Delegates said the United States was still holding out for a tight definition of health emergencies. It wanted to limit future use of the system to "infectious epidemics" like AIDS. But developing countries seek more flexibility.
Many African countries also find measures demanded by rich countries to guard against abuse, such as cheap drugs turning up on their black markets, too burdensome.
They also want the agreement to spell out clearly that medicines should include vaccines. The United States, attacked by health activists for allegedly doing the bidding of its big pharmaceuticals concerns, issued a statement saying it remained "committed to the spirit and intent of Doha".
