Rome: The UN food chief said on Saturday he was chilly but otherwise slept OK after his first night on a hunger strike to draw attention to the plight of the world's hungry before next week's UN food summit.

Jacques Diouf began the 24-hour strike at 8pm on Friday in the lobby of the Rome-based UN Food and Agriculture Organisation.

Since FAO offices are unheated at night, he donned a hat and scarf, and wore his overcoat over his pajamas as he spent the night on a makeshift mattress.

"I slept pretty well," Diouf said in a statement. "The only problem was the cold." Temperatures in the capital dipped to 8 C (46 F) overnight.

The FAO said Diouf was trying to show solidarity with the world's 1 billion chronically malnourished people, raise awareness about their plight, and put pressure on world leaders to do something about it.

FAO has said global food output will have to increase by 70 per cent to feed a projected population of 9.1 billion in 2050.

To achieve that, poor countries will need $44 billion yearly of aid to agriculture, compared with the current $7.9 billion, to increase access to irrigation systems, modern machinery, as well as to build roads and train farmers.

At the summit, world leaders are expected to pledge to increase agricultural development aid.

But a draft declaration already approved by delegates omits any specific financial commitments and doesn't include the 2025 deadline for eradicating hunger, which had been sought by the UN

Few heads of state from wealthy countries are attending, although Zimbabwe's Robert Mugabe arrived Saturday and other African leaders were expected. Pope Benedict XVI will address the summit on Monday.

Diouf, who continued the strike on Saturday, has called on people around the world to join in the hunger strike by skipping meals this weekend. UN chief Ban Ki-moon is expected to join the strike on Sunday.

"We have the technical means and the resources to eradicate hunger from the world so it is now a matter of political will, and political will is influenced by public opinion," Diouf said in the statement.