Democratic presidential candidate Barack Obama arrived in Iraq Monday, continuing a foreign tour that has already taken him to Afghanistan.

Obama's first stop was Basra, the centre for roughly 4,000 British troops involved mostly in training Iraqi forces, the U.S. Embassy confirmed.

Later, the Illinois senator met with Iraqi Prime Minister Nouri al-Maliki in the heavily protected Green Zone.

He is also expected to meet with the top U.S. commander in Iraq, Gen. David Petraeus, and other military chiefs Monday.

The officials are expected to outline the gains made in Iraq in recent months against both Shiite militia and Sunni insurgents -- including al Qaeda in Iraq.

The White House, military leaders and many Baghdad residents credit last year's troop surge in areas around Iraq's capital with shifting the momentum.

However, Obama did not support the surge and has been attacked on his position by Sen. John McCain -- the Republican presidential candidate.

If elected president, Obama has promised to remove troops from Iraq over a 16-month period.  He has been less precise on the U.S. military's role in the country after the exit.

"The senator is on a fact-finding mission and he'll come back and he'll evaluate with his top advisers (about) what he saw," Steven Cook, with the Council on Foreign Relations, told CTV's Canada AM on Monday.

Cook said Obama's mission will be a success if he comes back "without giving his opponent any ammunition to use against him throughout the campaign."

Meanwhile, Obama continues to press for a troop "surge" to help battle the increasingly deadly situation in Afghanistan.

On Sunday, Obama met with Afghan President Hamid Karzai, telling him the U.S. will fight terrorism "with vigour" if elected.

The senator sees the fight against the Taliban and al Qaeda in Afghanistan as the most important battle facing America.

Cook said Afghanistan has started to take centre stage in the U.S. because the situation has deteriorated there so rapidly in the last six months.

He also said Afghanistan is getting a higher profile because of all the attention the presidential candidates are putting on the country.

"Senator Obama has brought to attention that Iraq was a distraction from the central front in the war on terrorism which was being waged in Afghanistan and the Pakistan border," said Cook.

Obama is also expected to visit Europe and Israel during his tour.

Analysts say the international trip is part of an effort by the Obama camp to boost his foreign policy credentials. His Republican rival, John McCain, has questioned Obama's readiness to lead the U.S. on the world stage.

With files from The Associated Press