Millions of people risk facing famine in Yemen, the head of the World Food Programme (WFP) has said.

The UN agency said in a statement released on Wednesday, that the number of food insecure people in Yemen was now close to 13 million, adding that one in five of the country's population were suffering from severe food insecurity.

Children bearing brunt of war in Yemen

During her three-day visit, Ertharin Cousin, WFP's executive director, travelled to the capital, Sanaa, Aden and Amran, and met with displaced families and mothers with malnourished children.

She also held talks with the authorities on both sides of the front lines, WFP said.

Yemen's conflict pits the Houthis and troops loyal to former President Ali Abdullah Saleh against forces including southern separatists, tribal fighters and troops backing President Abd-Rabbu Mansour Hadi, who is in exile in Saudi Arabia.

The Saudis are leading a US-backed Arab coalition that is carrying out air strikes against Houthi fighters since March.



On Wednesday, a bomb attack on the governor's temporary headquarters in Yemen's main southern city of Aden on Thursday killed four people and wounded 10 others, security officials and medics said. Governor Nayef al-Bakri was unharmed in the blast at the headquarters of the Aden Faculty of Administrative Sciences, which is housing the governor's offices, the sources said.

Related: Turning point in Yemen's war?

Witnessing the challenges first-hand, Cousin warned that the lack of immediate and unhindered access to people who urgently need food assistance and the shortage of funding will create the possibility of famine for millions, mostly women and children, who are already suffering from hunger.

"Even before this crisis began, Yemen had one of the highest malnutrition rates in the entire world. What we're seeing now is an increase in the number of severe malnutrition cases because of lack of access of our programme operators to provide the support that is necessary.



"So what we're seeing now is we're trying to play catch-up, we're trying to play catch-up to save the lives of these children and to ensure the opportunity for them to receive the nutritious food that they require," Cousin said.

In #Yemen : 1 in 5 ppl need food assistance + child malnutrition is high. Fighting is making @WFP 's work even harder. pic.twitter.com/tINSCuiuMp — WFP Media (@WFP_Media) August 17, 2015

According to the statement, a recent vulnerability assessment conducted by WFP using mobile phone technology, reaching some of the households in areas inaccessible by teams on the ground, reflected that the deteriorating food security situation is particularly affecting the internally displaced families.

Many families are existing on bread, rice and tea.

One Minute Yemen

Human rights group Amnesty International said in a report that the Saudi-led air campaign had left a "bloody trail of civilian death" which could amount to war crimes. It said it had investigated eight coalition air strikes in Yemen that killed 141 civilians, including children.

Evidence revealed a pattern of strikes against populated areas, in most of which no military target could be located nearby, it said.

The coalition has denied targeting civilians.

Loyalist forces, backed by Gulf Arab planes, weapons and training, have been on the offensive since breaking out of Aden last month, claiming a string of gains against the Houthis.

WFP has already reached 3.5 million people with food since the beginning of the conflict but the fighting makes deliveries difficult and dangerous.

Many road networks in the hardest hit areas of the country are still not operational making communities in conflict-areas inaccessible for aid workers, the agency said.