DAMASCUS, Syria (CNN) -- Syrian President Bashar Al-Assad denied Wednesday that he or his country was involved in the February assassination of former Lebanese Prime Minister Rafik Hariri.In an interview with CNN's Christiane Amanpour, Al-Assad said such an act would go against the principles and interests of Syria as well as his own values."I would never do such a thing in my life. What do we achieve?" Al-Assad asked. (Transcript)"I think what happened targeted Syria. That would affect our relation with the Lebanese people and with most of the country. So we wouldn't do it because it's against our interest, and it's against my principle. I would never do it. It's impossible." (Watch Al-Assad express confidence Syria wasn't involved in the killing -- 4:21) Al-Assad also denied reports that he had threatened Hariri and demanded that the former prime minister support a term extension for Lebanese President Emile Lahoud, a Syrian supporter."I'm a very quiet person. I'm very frank, but I wouldn't threaten," he said.Al-Assad argued Syria didn't have the motive to kill Hariri, whom he said helped Damascus by working to keep Lahoud in power longer.A U.N. investigation is trying to determine if Syria played a role in the February 14 bombing that killed Hariri. He had opposed Syria's decades-long presence in Lebanon, and his death sparked protests that led to Syria's withdrawal in April. Investigators will report their findings within two weeks.Al-Assad said that if the U.N. investigation concludes Syrians were involved, those people would be charged with treason and face an international court or the Syrian judicial process. Speaking in fluent English, Al-Assad bristled at a question suggesting that he may not be fully in charge of his country or not "in the loop" regarding alleged retribution for those who speak out against the government."But at the same time, they say that I'm a dictator," he said. "So they should choose. You cannot be a dictator and not in control. If you're a dictator, you're in full control. And if you're not a dictator -- if you're not in control, you cannot be a dictator."He said his authority is dictated by the country's constitution, but he also encourages dialogue within his government before he makes crucial decisions.Regarding Syria's eastern neighbor, Iraq, Al-Assad said the United States should re-examine its policy there because of the negative consequences of the war."We should re-evaluate what's going on in Iraq," he said. "What did we achieve, what did they achieve from that war in Iraq," he asked. "It's a very simple question. What did they achieve economically, politically, fighting terrorism? (Watch Al-Assad tell Amanpour why he disagrees with U.S. policy -- 1:51) "We didn't achieve anything. This is one example."When Amanpour suggested the U.S.-led war ousted Saddam Hussein, Al-Assad replied, "Yeah, but what did you lose as a return? The hope of the people, the stability, no better democracy, no better economy, no services, no stability in the region, more terrorism -- so is that the prize you've won for getting rid of a dictator? That's not a goal."Al-Assad's regime has faced sharp criticism from the United States, which has alleged the country shelters terrorist organizations and has failed to take measures to prevent fighters from crossing the border into Iraq.On Wednesday, President Bush called on Syria to be a "good neighbor" in the Middle East, warning Damascus against interfering in Lebanon and allowing insurgents to cross into Iraq. "We're making good progress toward peace in the Holy Land, but one of the areas of concern is that foreign countries such as Syria might try to disrupt the peace process by encouraging terrorist activities," Bush said. (Full story)"We expect Syria to do everything in her power to shut down the transshipment of suiciders and killers into Iraq." Al-Assad said that the United States cannot control its border with Mexico so Syria cannot be expected to keep people from sneaking into Iraq.He said his country does not support people who kill Iraqis but he thinks there is a difference between terrorists and those who fight against American and British troops.He added that his country has asked Washington for technical support to monitor the Iraqi border better but ended its security cooperation with the United States recently because of repeated verbal attacks from the Bush administration.The interview was conducted just before the news of the suicide of Ghazi Kanaan, Syria's interior minister who led the country's military intelligence in Lebanon for nearly 20 years. (Full story)Kanaan died in a Damascus hospital of a gunshot wound to the head, according to the interior ministry and other government ministers. The official was among those interviewed by a German prosecutor heading the U.N. investigation into Hariri's death.