From an aircraft carrier in the Persian Gulf, US Vice President Dick Cheney warned Iran that the US and its allies will keep it from restricting sea traffic as well as from developing nuclear weapons. "We'll keep the sea lanes open," Cheney said Friday from the hangar deck of the USS John C. Stennis as it steamed about 150 miles (240 kilometers) from the Iranian coast. Cheney is touring the Middle East asking Arab allies to do more to help Iraq and to curb Iran's growing power in the region. With Iraq in turmoil, both Iran and Saudi Arabia are maneuvering to see who can help fill the leadership vacuum. The American vice president made clear the United States' intentions on the rivalry. "We'll stand with others to prevent Iran from gaining nuclear weapons and dominating this region," he said. On Saturday, Cheney will make a fence-mending visit to Saudi Arabia. The oil-rich kingdom, long a key American ally in the Middle East, recently has been shunning the US-supported government of Iraqi Prime Minister Nouri al-Maliki, suggesting he is too close to Iran. Before leaving for Saudi Arabia, Cheney is expected to press Emirates President Sheik Khalifa bin Zayed Al Nahyan to support US efforts in Iraq and to shut down Iranian companies in his country that US officials believe are backing Iran's nuclear development. Some 500,000 Iranians live in the United Arab Emirates. Roughly a quarter of the world's oil supplies pass through the narrow Straits of Hormuz connecting the Persian Gulf with the open waters of the Arabian Sea. Iran controls the eastern side of the straits. With two US carrier groups now in the region, Cheney declared Friday, "We're sending clear messages to friends and adversaries alike. We'll keep the sea-lanes open. "We'll stand with our friends in opposing extremism and strategic threats. We'll disrupt attacks on our own forces," he added. US officials have said that some of the sophisticated roadside bombs used against US troops in Iraq have come from Iran. After returning from the carrier, Cheney had dinner with Emirates Crown Prince Sheik Mohammed bin Zayed Al Nahyan. Cheney's visit comes just two days before Iranian President Mahmoud Ahmadinejad is to visit Abu Dhabi. Ahmadinejad wants the Emirates and other Gulf Arab countries to drop their military alliances with Washington and join Iran in regional efforts. The United States has about 40,000 troops on land bases in Gulf countries outside Iraq and about 20,000 sailors and Marines in the region. No Gulf state has yet backed Iran's offer of an alliance.