The UN chief criticized Sudan Monday for expelling aid agencies in Darfur at a speech to an Arab summit attended by the defiant Sudanese president, who dismissed international war crimes charges against him. The nearly back-to-back speeches at the opening of an Arab League summit were the first direct encounters between Sudanese President Omar al-Bashir and UN Secretary-General Ban Ki-Moon since the International Criminal Court issued an arrest order for al-Bashir earlier this month on the war crimes charges. The encounter highlighted the vast divide over al-Bashir - with fellow Arab leaders rallying behind him, and the backers of the court left widely powerless to bring him to justice as long as he remains in friendly territory. "Relief efforts should not become politicized," Ban said in a speech to the summit attended by al-Bashir. "People in need must be helped irrespective of political differences," he added in an appeal to resume relief efforts to Darfur. Al-Bashir attacked the UN Security Council - which asked the international court to open the Darfur war crimes investigation. He called it an "undemocratic institution that ... applies double standards, targeted the weak and gave a blind eye to the (real) criminals." He claimed the United Nations cannot keep its credibility "with some countries having hegemony." Al-Bashir had a receptive audience. He arrived Sunday in Qatar - embraced by the tiny Gulf nation's emir at a lavish airport ceremony. Earlier this month, the 22-member Arab League made clear it would not arrest al-Bashir if he attended the summit, saying that would only enflame the conflict between the Arab-led government in Sudan and ethnic Arab rebels in Darfur. The United Nations estimates that the fighting has killed up to 300,000 people and driven 2.7 million from their homes since 2003. Only Jordan and two other tiny Arab League members, the Comoros and Djibouti, are parties to the ICC charter, but they can take no action on Qatari soil. Arab foreign ministers have endorsed a draft resolution for the summit rejecting the ICC's arrest warrant issued on March 4. Syrian President Bashar Assad urged the summit to "take a daring, clear and direct stance that rejects and doesn't compromise" on the ICC charges. He also called the ICC decision part of "attempts to divide Sudan." Al-Bashir also offered no sign that he would allow the return of international aid groups expelled after the ICC decision. Ban told the Arab leaders that "we must also work together to transcend the tensions related" to the court, which was established at a UN conference in Rome in 1998. The ICC is independent from the world body and relies on nations backing the ICC charter to carry out its decisions. The UN Security Council can - as it did with Darfur - ask the court to launch an investigation into alleged war crimes. The council can also suspend a case for a year, though it has never done this. Ban said the UN-aided peacekeeping mission in Darfur still lacks "critical assets" and "cannot substitute for a political process." In February, Qatar mediated preliminary contacts between Sudan's government and the most powerful Darfur rebel group, but there has been little progress since. Before the opening of the Arab summit, a coalition of Middle East human rights groups urged leaders not to protect Sudanese officials accused of atrocities in Darfur - a direct jab at support for al-Bashir. "There should be no immunity for those who have committed crimes in Darfur," said the declaration by the Arab Coalition for Darfur, signed by 15 groups from across the region. Another top goal of the summit was to heal Arab divisions over issues including Iraqi reconstruction, internal rifts among Palestinians and how to confront perceived threats from Iran's expanding influence in the Gulf and elsewhere. Saudi Arabia and other nations favor a stronger approach against Shiite Iran. But others, particularly smaller Gulf nations, are trying to strike a balance between Iran's growing political ambitions and their traditional ties to the Sunni Arab world. Egypt's president, Hosni Mubarak, stayed away from the summit in Qatar - which has been at odds with Cairo over rival approaches to Darfur and the Palestinian struggles between Iranian-aided Hamas and Western-backed leader Mahmoud Abbas. At the opening session, Libyan leader Moammar Gadhafi stormed out after denouncing Saudi's King Abdullah for his long ties to the West. Gadhafi has harbored a grudge against Abdullah since exchanging harsh words during a summit in 2003 shortly before the US-led invasion of Iraq, which Gadhafi strongly opposed. The Libyan leader is known for his unpredictable behavior.