The Venezuelan president, Hugo Chavez, is due to arrive in Baghdad today, defying western objections and delivering a propaganda coup for the Iraqi leader, Saddam Hussein.

Mr Chavez will be the first elected head of state to meet Mr Saddam since the 1991 Gulf war. Iraq yesterday hailed the visit as a slap in the face for the United States.

"Every now and then, the rulers of America receive slaps from representatives of other countries," an Iraqi foreign ministry spokesman said.

Venezuela says the visit is justified because it holds the rotating presidency of the Organisation of Petroleum Exporting Countries (Opec), of which Iraq is a member.

On Monday, the US state department said it was "deeply concerned" about the planned meeting with President Saddam, but Venezuela insisted that the president would not change his plan. "Nobody can influence our decision. He's going to arrive, whether it be on a skateboard or on a camel," Jose Vicente Rangel, the foreign minister, said.

Mr Chavez is expected to travel by land from Iran to avoid the UN-imposed air embargo. But the Americans accuse him of breaking political sanctions, and say that he did not seek advice from the UN sanctions committee before deciding on the visit.

In Britain, Ann Clwyd MP, the chairwoman of Indict, the organisation which is seeking to prosecute leading members of the Iraqi regime, described the trip as a bad move.

"I would remind democratically elected presidents of the Iraqi regime's record - it is one of the worst since the second world war," she said. "People forget and start treating [Iraq's leaders] like ordinary human beings. That's why it's important that the UN does set up a war-crimes tribunal and stops dragging its feet."

Iraq was preparing a ceremonial welcome yesterday for the man it described as "a dear guest", and was laying on special facilities for the foreign media to maximise the west's embarrassment.

Mr Chavez is touring Opec countries handing out invitations to Caracas next month for what he hopes will be the organisation's first heads-of-state summit for 25 years. He has already visited Saudi Arabia, Kuwait and Qatar.

Under American pressure, the Saudis have been seeking to increase Opec oil-production quotas, to reduce prices from their peak of around $30 (£20) a barrel. But Venezuela - which at 3.1m barrels a day is Latin America's largest producer - is almost totally dependent on oil revenue, and each $1 drop in oil prices costs it about $1bn (£665m) a year.

Mr Chavez argues that the real issue is not high prices, but fair prices.

"We understand that they [consumers] start to feel uneasy when crude oil prices reach $30 a barrel, but they can imagine how it must have been for us when it fell to $8," he said recently.

Last month, in a presidential election which the US described as free and fair, Mr Chavez was re-elected with around 60% of the vote. He is a charismatic, populist leader who, despite high oil prices, has failed to deliver economically.

During the election, he promised an "economic revolution" to get the economy back on its feet and give the poor - his main source of support - a larger share in oil-generated profits.