The minister, Mohammed Mehdi Saleh, said supplies distributed so far should ensure everyone had a stockpile to last three months.
"And we are going to increase the quantity in the coming months so that everybody is secured in this regard," he said.
UN arms inspectors, on a mission that may prove crucial in deciding whether a war takes place, checked at least three sites for signs of weapons of mass destruction and questioned scientists at Baghdad's Technological University.
The inspectors, whose next report to the UN Security Council is due on January 9, have not taken a break for a Christmas season marked by appeals for peace from Christian religious leaders.
The pressure for rapid and aggressive inspections has come from the United States, which has threatened to go to war if Iraq cannot prove it has scrapped all its nuclear, chemical and biological weapons programs, as required by UN resolutions.
Their final report is due by January 27. With Iraq continuing to insist it no longer has the capacity to develop weapons of mass destruction, speculation is growing the report could be the trigger for war.
Israel's military intelligence chief, Major-General Aharon Ze'evi-Farkash, told a parliamentary committee in Jerusalem this week that any US assault on Iraq was likely to be in early February.
Relief agencies already fear a major humanitarian crisis in a country badly damaged by over a decade of UN economic sanctions since its invasion of Kuwait in 1990.
Saleh said Iraq had earlier this year begun giving each family double rations of basic foodstuffs including wheat, rice, cooking oil and milk powder every other month.
Saleh said his ministry was taking measures to ensure the local market functioned if there was a war.
He also issued a warning to the United States: "We have taken measures to defend our country, our land and it (war) will not be a picnic. ... They will face hardship, difficulties and big losses if any aggression takes place and they will not achieve any objective from the war."
George Robertson, the secretary-general of the transaTlantic NATO alliance, said he expected it to support any US-led campaign against Iraq, with or without United Nations approval.
"(NATO) is very, very supportive of the United Nations process and if that breaks down, then clearly there is a moral obligation by NATO to give whatever support is required," he told BBC Radio.
So far Britain is the only NATO member to express readiness to join a US-led war in Iraq, although it has said it would prefer to have it endorsed by the UN Security Council.
Pope John Paul, spiritual leader of a billion Roman Catholics, appealed to the world in his Christmas Day message from the Vatican to avert conflict in Iraq.
He said people were called on in the Middle East to "extinguish the ominous smouldering of a conflict which, with the joint efforts of all, can be avoided."
The UN inspectors, who resumed their work in Iraq last month after a tough UN resolution pushed through by the United States, have had no time for seasonal reflection or celebration.
On Christmas Day they visited seven suspect sites, and yesterday Iraqi officials said they had questioned department heads and the dean of Baghdad's Technological University.
They also checked equipment tagged by previous inspection teams at a laboratory of the chemical engineering department.
The dean, Mazen Joumaah, told reporters the inspectors were "highly professional and knew what they wanted".
He said they had asked his staff for precise details of the curriculum in various subjects at the college. With their mission in its fifth week, the inspectors have now completed more than 170 missions, visiting many sites more than once.
In the first round of inspections in the 1990s, after Iraq's defeat in the Gulf War, the United Nations destroyed tons of Iraqi chemical and biological weapons and dismantled Iraq's nuclear weapons program.
As the inspectors made their rounds, Iraq's Christian minority celebrated Christmas with prayers and carols.
"Yesterday and today I prayed for peace," said Father Boutros Hadad at the Chaldean Virgin Mary Church in Baghdad. "The theme was: Don't be afraid, God is with us, he will rescue us."
Outside the church, worshippers sang Christmas carols and women lit candles and distributed sweets.
Few Christmas trees could be seen in Baghdad, and only Christians take the day off.
Christians represent about 5% of Iraq's 22 million population, living mainly in Baghdad.