Tunisia's largest union on Monday attacked the government's handling of negotiations with the IMF on a loan to bail out the North African country as it slides deeper into debt.

Tunisia is seeking a bailout package worth nearly $2 billion from the International Monetary Fund, which conditions any aid on a series of reforms.

As Noureddine Taboubi of the Tunisian General Labour Union (UGTT) was giving his May Day speech in the capital Tunis, protesters in the country's second city Sfax denounced "an IMF government", saying "No to colonisation".

Representatives of nearly two dozen countries and international institutions met Monday in Qatar for talks on Afghanistan focusing on women's rights under the Taliban administration, the United Nations said.

The Taliban authorities are absent from the closed-door two-day meeting, and UN spokesman Stephane Dujarric said recognition of their rule "is not up for discussion".

The UN on Monday warned more than 800,000 people could flee fighting and dire conditions in Sudan, where explosions again shook the capital in violation of the latest truce extension agreed by warring generals.

The chaos and bloodshed, now in their third week, have already sparked an exodus of tens of thousands of Sudanese to neighbouring countries including Egypt, Chad and Central African Republic.

But the United Nations' refugee agency, UNHCR, said it was bracing for "the possibility that over 800,000 people may flee the fighting in Sudan for neighbouring countries".

Hasan Faraj was brushing his teeth on the morning of April 15 when gunfire erupted outside his building near Khartoum's airport, early shots in a war that caught him totally unprepared.

The Pakistani national had recently handed in his passport to a government office, complicating any effort to leave, and his paltry stash of food and other supplies meant he would struggle to wait out the fighting at home.

The top United Nations humanitarian official is heading to the Sudan region due to the "rapidly deteriorating humanitarian crisis" in the conflict-racked country, the UN chief said.

Secretary-General Antonio Guterres' announcement Sunday came shortly after rival Sudanese forces announced the extension of a truce they have largely violated, as warplanes roared overhead and fighting continued in the capital Khartoum.

UN chief Antonio Guterres will gather international envoys at a secret location in Doha on Monday in an increasingly desperate bid to find ways to influence Afghanistan's Taliban rulers.

Considered the world's biggest humanitarian crisis by the United Nations, Guterres's quandary has been deepened by the Taliban administration's move to stop girls going to school and most women from working, even for UN agencies.

Hikes in import and export tariffs imposed by the Islamist rulers of the Gaza Strip since last year have fuelled discontent among merchants in the impoverished, blockaded territory.

In March, Gaza's Hamas rulers imposed new duties on the import of fruit and the export of fish.

Although the fruit levy was later reversed after traders went on strike, the seafood duty remains. Traders refusing to pay risk having their perishable goods stalled at crossing points from the enclave.

The latest protest against the Israeli government's controversial judicial reform plans packed central Tel Aviv on Saturday, as divisions persist before lawmakers return to parliament.

Opponents of the legislation have kept up demonstrations in the commercial hub and across the country since January, despite Prime Minister Benjamin Netanyahu putting the controversial reform programme on ice a month ago.

An interminable row of minibuses lines the road that separates Sudan's southeastern city of Gedaref from the Ethiopian border, slowly bringing people fleeing Sudan's war closer to safety.

There, families have been "sleeping on the ground out in the open", said Oktay Oglu, a Turkish engineer who worked at a factory in the capital Khartoum before escaping with his family.

Locals and foreigners alike have made this journey, fleeing more than two weeks of brutal fighting that pits forces loyal to rival generals against one other, with civilians caught in the crossfire.

The first Iranian evacuees to escape the Sudan conflict through Saudi Arabia arrived on Saturday in Jeddah, relieved that their country has settled its differences with the regional rival.

The 65 Iranians were among about 1,900 people on the latest boat to arrive from Port Sudan as the battle between rival Sudanese forces entered a third week.

Saudi Arabia has so far organised evacuations for about 5,000 people from 96 countries, according to the foreign ministry.