On Mustafa al-Kadhimi's visit, his first trip since taking office in May, he pledged to protect Iran from attacks. IraqiPrime Minister Mustafa al-Kadhimi said on a trip to Tehran on Tuesday that Iraq would not allow any aggression against Iran coming from its territory. Speaking at a news conference alongside IranianPresidentHassan Rouhani, al-Kadhimi alluded to Iraq's concern not to become a battlefield between arch-enemies Iran and the United States. The Iraqi prime minister faces a tough balancing act between Tehran and Washington, which have come close to open conflict in the region, particularly on Iraqi soil, over the past year. At home, al-Kadhimi faces increasing pressure from Iran-aligned groups that perceive him as siding with the US, because he has indicated he wants to curb the power of Iranian-backed militias and political parties. "The people of Iraq want good relations with the Islamic Republic of Iran based on the principle of non-interference in the internal affairs of both countries," he told the news conference, carried live by Iranian state television. "Iraq is a country that won't allow any aggression or challenge to Iran from its territory." Balancing act Al-Kadhimi rose to the premiership in May after serving as head of Iraq's National Intelligence Service for nearly four years. He formed close ties to Tehran, Washington and Riyadh during that time, prompting speculation he could serve as a rare mediator among the capitals. In his first two months in office, Iraqi security forces carried out two arrest raids against militias but most of those detained were quickly released. The United States praised those moves and supporters welcome several appointments al-Kadhimi has made in the security forces, including reinstating Iraq's Counter Terrorism Service chief Abdul Wahhab al-Saadi, whose dismissal under the previous government fuelled mass anti-government unrest last year. Iranian Foreign MinisterMohammad Javad Zarif visited Baghdad on Sunday, making a stop at the site where a US drone strike killed Iranian GeneralQassem Soleimani and Iraq's paramilitary chief Abu Mahdi al-Muhandis in January. That attack brought the region to the brink of a full-blown US-Iran conflict before both sides stepped back. Iran's Supreme LeaderAyatollah Ali Khamenei, during a later meeting with al-Kadhimi, praised the Popular Mobilisation Forces, an Iraqi state-controlled institution that is an umbrella grouping of militias, many backed by Iran. Khamenei also said Iran would not interfere in relations between Iraq and the United States, according to his official website. However, the supreme leader vowed Iran would "strike a reciprocal blow" against the US for Soleimani's killing. 'Heroes' Rouhani hailed as "heroes" his top Iranian general and the Iraqi commander killed together in the US drone strike on Baghdad airport at the start of the year. "I deem it necessary to honour the two heroes of the fight against terrorism, martyrs General Qassem Soleimani and Abu Mahdi al-Muhandis," he said. Rouhani described them as having "worked for Iraq's security in previous years" - a reference to Baghdad's fight against the armed group, ISIL (ISIS). Renad Mansour, a senior research fellow at Chatham House, said some Iranian officials believed al-Kadhimi may have played a role in the US drone killings as head of the national intelligence service. "It was a very bad relationship at that time, but over the months Iran also felt with all the chaos they needed someone so a compromise was made, and Iran begrudgingly had to agree and help facilitate his premiership," Mansour told Al Jazeera. "Clearly it a is a very fragile relationship and the more he goes against Iranian interests in Iraq - whether it's going against their militia allies or economic practices - there will be a lot of back-and-forths and tit-for-tats I would say." 'Turning point' Relations between the two countries were not always close - they fought a bloody war from 1980 to 1988. Tehran's influence in Baghdad grew after the 2003 US-led invasion of Iraq toppled the government of Saddam Hussein. Al-Kadhimi's visit, his first foreign trip since taking office in May, was meant to come after a trip to Saudi Arabia but that was cancelled after the Saudi king was admitted to hospital suffering from inflammation of the gall bladder. Rouhani called the visit by Iraq's new prime minister a "turning point" in the countries' relations and vowed to continue supporting the neighbouring Arab nation. The official website of the office of the Iranian presidency later released a photo of Rouhani and al-Kadhimi at a welcome ceremony in Tehran, showing both wearing protective face masks to help prevent the spread of the coronavirus. "We are certain that the visit will be a turning point in relations between the two countries," Rouhani said after meeting with the Iraqi leader. "We still remain ready to stand by the Iraqi nation and apply efforts for stability and security in Iraq and the region." Al-Kadhimi said Iraq's foreign policy is based on "balance and avoiding any alignment". $20bn trade As a former intelligence chief backed by Washington, al-Kadhimi took office in May after he played a significant part for years in the war against ISIL, which was defeated in Iraq in 2017. Rouhani said Iran and Iraq hoped to boost bilateral trade to $20bn yearly. Iran sees Iraq as a possible route to bypass US sanctions that President Donald Trump reimposed on Tehran in 2018, after pulling the United States out of the 2015 nuclear deal with world powers. Last year, Iran's exports to Iraq amounted to nearly $9bn, the official IRNA news agency reported Tuesday. Under former dictator Saddam Hussein, Iraq waged an eight-year war in the 1980s against Iran - a conflict that left nearly one million dead on both sides.