The World Trade Organization's 13th ministerial conference (MC13) in Abu Dhabi entered its last scheduled day on Thursday, with major issues still stuck in the weeds.

The WTO meeting in the capital of the United Arab Emirates had opened on Monday with major disagreements between the body's 164 member states on key issues.

They include fisheries subsidies, agriculture and a moratorium on customs duties for digital transactions, which dominated the agenda of the talks.

As of Thursday morning, there were no major signs of a breakthrough, with a formal closing session initially scheduled for 8:00 pm (1600 GMT) pushed to midnight (2000 GMT).

"Everybody is working with a very positive try to see what's the maximum we can get done," Indian commerce minister Piyush Goyal told journalists.

"I am very confident...we will come out with significant outcomes, particularly when it refers to areas of very deep concern to large numbers" of developing countries, he added.

Eyes are trained on tradeoffs as part of a potential package deal that could allow for greater convergence, as was the case during the 2022 ministerial meeting in Geneva.

A new deal on fisheries was initially viewed as the most likely outcome of the talks. But Goyal on Thursday said "it is very difficult to get a resolution."

A draft text of a deal that was meant to be circulated on Wednesday is still facing delays, said a source close to the negotiations who spoke on the condition of anonymity.

The overall negotiations "are a bit like a rollercoaster," said the same source.

Another sticking point is over the extension of an e-commerce moratorium.

Since 1998, WTO members have agreed not to impose customs duties on electronic transactions.

The moratorium has been extended at most ministerial meetings since then, but objections by India and South Africa are now throwing it into jeopardy.

When asked if India would compromise on an extension, Goyal said "let's see what the others are budging on."

But he warned that an extension can't be "taken for granted."

On food security, Goyal said he was "confident" progress could be made on permanent rules governing public stockholding of food reserves -- a key demand of India.

A "solution can be achieved," Goyal said.