Press TV - Some 53 percent of Yemen�s population, 15.9 million people, is now facing �severe acute food insecurity� as the direct result of a Saudi-led invasion of the impoverished country and the ensuing economic collapse, a survey says.

The survey, whose results were published on Saturday, was conducted by Yemeni officials and international experts during the month of October based on the Integrated Food Security Phase Classification (IPC), also known as IPC scale.

According to the IPC�s five-point scale, 3 stands for �crisis�, 4 is for �emergency� and 5 is used to refer to �catastrophe� and possible famine.

The survey warned that the 15.9 million people now in phases 3-5 could eventually reach 20.1 million people, 67 percent of the population, if there is not adequate food aid. The number in �catastrophe� would triple to 238,000.

The results held the nearly four-year-long imposed war responsible as the main culprit of the hunger crisis, exacerbated by extremely high food prices, a liquidity crisis, disrupted livelihoods, and high levels of unemployment.

The survey also said that food aid, provided by the United Nations and other aid groups, was not enough to plug the gap.

�Immediate responses are required to save lives and livelihoods of millions not to slide to the next worse case which is famine,� it said.

The results further showed the presence of many pockets of extreme hunger across Yemen, concentrated in areas with active fighting, particularly in western and northern regions. They also warned that without humanitarian aid, 13 provinces would be in a food catastrophe.

Some of the results of the survey were released by the UN on Thursday.

The report was released as the UN brought Yemen�s warring sides together for the first peace talks in two years in Sweden.�The Houthi Ansarullah movement has strongly rejected demands by its rival group, the country�s former Saudi-backed government.

Mohammed Abdulsalam, the head of the Houthi delegation at the peace talks, called on the sidelines of the negotiations on Saturday for the formation of a transitional government with the participation of �all political parties.�

He also said Yemen�s vital port city of Hudaydah, currently under a tight blockade by the invaders, should be declared a �neutral zone.�

As for the international airport of the capital Sana�a, Abdulsalam said that his movement was open to the possibility of giving the UN a role at the airport as part of an effort to get it reopened. The airport is currently under an imposed closure by the former government and the coalition led by Saudi Arabia.

On Friday, the Houthi delegation strongly rejected its rival group�s proposals of handing over the port city and inspecting�flights to Sana�a airport. The Saudi-led coalition, which has so far bombed the airport several times, has tightly restricted access to the airport. It also controls the air space.

The so-called government, led by Yemen�s former President Abd Rabbuh Mansur Hadi, a staunch ally of Riyadh, has tightly besieged Hudaydah through its armed militia and mercenaries employed by the United Arab Emirates since June, when they launched a full-scale offensive against the western port city.

Since the onset of the operation against Hudaydah, the humanitarian situation has worsened in Yemen due to a broad economic collapse. More than 70 percent of Yemen's imports used to pass through the docks of the vital port.

The invaders have failed to achieve their objective of overrunning Hudaydah and defeating Houthi fighters.

Leading a coalition of its allies, including the UAE and Sudan, Saudi Arabia invaded Yemen in March 2015 in an attempt to reinstall Hadi, who had resigned amid popular discontent and fled to Riyadh.

The imposed war initially consisted of an aerial campaign�but was later coupled with a naval blockade and the deployment of ground mercenaries to Yemen.

Since the onset of aggression, the Yemeni army, backed by fighters from Ansarullah, has been defending the impoverished nation against the invaders. The coalition is also resolute to crush the movement as another goal in its war on Yemen, which is teetering on the edge of famine.

The aggression is estimated to have left 56,000 Yemenis dead.

Riyadh had declared at the start of the invasion that the war would take no more than a couple of weeks.