Leaders of the G20 nations are holding an extraordinary meeting on Tuesday to address the growing humanitarian and security crisis in Afghanistan.

Rome is hosting the meeting, where topics are to include new terrorist threats, as well as how to deal with the Taliban.

The situation in Afghanistan has dramatically deteriorated since the hard-line Islamists seized power in the country following the withdrawal of US and other Western troops after a nearly 20-year occupation.

Governments worldwide are now debating how best to help the population, as some 3.5 million people are internally displaced. Other concerns include whether to recognize the Taliban, given the Islamists' dire record on human rights.

During the weekend, the US Department of State held the first-ever face-to-face discussions between the Taliban and US officials, in what the latter called a "candid and professional" exchange.

The talks focused on security and terrorism concerns, safe passage for US citizens, other foreign nationals and Afghan partners, as well as on human rights, according to a State Department spokesperson.

Meanwhile German Chancellor Angela Merkel called on leaders to "prevent a humanitarian catastrophe," in talks with Italian Prime Minister Mario Draghi in Rome, as she greeted the summit that he had initially proposed in August.

Since then, foreign ministers carried out preparatory work for the summit on the sidelines of the UN General Assembly.

Afghanistan urgently needs financial aid from abroad, otherwise many fear catastrophe, given a looming drought and the winter ahead.

There are growing concerns that the country's economy, health and banking systems are on the brink of collapse.

The UN recently warned 1 million Afghan children are at risk of starvation as winter approaches. More than half of the children under the age of five are at risk of malnutrition.

Some 18 million Afghans - half the total population - depend on humanitarian aid, according to the UN, with 93 per cent of households lacking enough to eat.

Meanwhile more than 2 million Afghans have fled to neighbouring countries.

Alongside leaders from the 20 most important industrialized countries, representatives of the European Union, the United Nations and international organizations have also been invited to attend the conference.

At a donor conference held last month, leaders pledged more than 1 billion dollars for the war-torn country, but according to UN High Commissioner for Refugees Filippo Grandi, only 35 per cent of this sum has so far been disbursed.

dpa