Top Iranian leaders have in the past two days pledged help for Iraq to restore peace and security to visiting Iraqi Prime Minister Nuri al-Maliki, while insisting that the withdrawal of U.S. forces from the war-torn country is vital to its security and stability.

Iran's President Mahmoud Ahmadinejad pledged Iran's role in keeping the stability of the region, which, largely hinges on the stability of the neighboring Iraq.

"The current situation in the region today, including Iraq, is very sensitive, Iran and Iraq have a heavy responsibility to establish peace and security in the region," said Ahmadinejad during his meeting with Maliki on Wednesday night.

"We counts on the victory of Iraqis for the future of the region," he added.

According to Iran's state media, Secretary of Supreme National Security Council Ali Larijani, during his meeting with Maliki, also pledged "Tehran's willingness to help Iraq solve its security problem."

First Vice-President Parviz Davoudi also told Maliki on Wednesday that Iran has always tried to restore security to Iraq because the country's security will benefit both Iran and the region.

For his part, Maliki said Iran was "positive and constructive" in helping his government to bring security in the war-torn country, underlining that "Iran, Iraq and other countries in the region must fight against terrorism."

However, U.S. President George W. Bush on Thursday voiced disagreement with Maliki's statement regarding Iran's "constructive" role in Iraq.

"If the signal is that Iran is constructive, I will have to have a heart to heart with my friend (Maliki) the prime minister because I do not believe they are," Bush said at a White House news conference.

While the Shiite Iraqi prime minister won great gestures and pledges of friendship and support from Iran, he was told by the Iranian leaders that the U.S. forces must leave his country.

In Iran's holy city of Mashhad, Iranian Supreme Leader Ayatollah Ali Khamenei on Thursday told Maliki the existence of U.S. troops was the biggest obstacle to restoring security in Iraq.

"The occupiers claim that if they exit now, Iraq will be destroyed. Whereas if the occupiers leave, all the Iraqi officials will move with full force to solve the people's problems," Khamenei was quoted by the state television as saying.

"The U.S. policy will definitely fail and the Iraqi people will be the victors in this arena," he added.

Maliki arrived Tehran Wednesday morning on a three-day visit for talks with Iranian leaders on improving the security situation in his country.

This is Maliki's second visit to Iran since his taking office in 2006.

Upon his arrival, Maliki was welcomed by Iranian Minister of Energy Parviz Fattah, with the presence of a large number of foreign ambassadors.

The United States has repeatedly accused Tehran of supporting Iraqi insurgents to fight with coalition forces and the Iraqi government. Iran denies such accusations, saying Washington was trying to find excuses for its failed policy in the Mideast.

Editor: Donald