In an exclusive interview with ABC News, Secretary of State Condoleezza Rice says the United States has "firm evidence" that last week's deadly suicide bombing in Tel Aviv was planned and coordinated from within Syrian territory by Islamic Jihad.
Rice, who was in London to attend an international conference on Palestinian security, also pressed Syria to pull out of Lebanon and take a tougher line against anti-Israeli terrorist groups and Iraqi insurgents based on Syrian soil.
And she said that the recent Iraqi election may have spurred recent democratic events in Lebanon and Egypt.
Until now, U.S. officials had not directly linked last week's deadly attack on a Tel Aviv nightclub to Syria, pointing instead to the supportive climate provided by the Syrians to Palestinian terrorist groups based inside Syria.
Today, Rice couldn't have been clearer. "There is firm evidence that Palestinian Islamic Jihad sitting in Damascus not only knew about these attacks, but was involved in the planning," she said.
She also said the United States would be "prepared to talk with others, with the Israelis, with the Palestinians, with others in the region about this."
Islamic Jihad has claimed responsibility for last Friday's attack that killed five Israelis and wounded more than 50 others. The attack had caused concerns it could derail the newly renewed peace process between Israel and the Palestinian Authority.
Shortly after the attack, Palestinian security officials blamed "a third party" for the attack, a veiled reference to Syria, which allows Islamic Jihad to operate from its territory. But, they had not directly said what evidence they had to prove that claim.
Even today, Palestinian Authority President Mahmoud Abbas said at a London news conference he still didn't have enough information as to who may have been responsible for Friday's bombing.
Rice told ABC News that though the extent of Syrian involvement in planning the attack is unknown, "Syria needs to be more accountable."
Stepping up the heat on Syria, she added, "the Syrians have a lot to answer for" and need to be more active in fighting "Palestinian rejectionists, if indeed they want to support the peace process as they say they do. What we need is for Syria to take its obligations not to support terrorism."
Rice would not respond to the question of whether the United States would tolerate a unilateral Israeli strike on Syria, saying, "I don't think that's a question we should even consider." But she added, "The Syrians know what they need to do."
Rice also called on the Syrians to be tougher on Iraqi insurgents based in Syria. "When you think about it, you have the territory of Syria being used to support an insurgency in Iraq, for Iraq that is clearly standing in the way of a better life for the Iraqi people, who vote overwhelmingly for that better life," she said.
Rice was also firm in warning Syria not to interfere in the upcoming Lebanese elections, noting "a lot has happened in Lebanon in the last two or three days, and what the Lebanese people should know is that the international community stands with them in their desire and aspirations for free and fair elections."
There have been massive demonstrations in Lebanon following the Feb. 14 assassination of opposition politician Rafik Hariri. Many Lebanese blame Syria for his death. On Monday, the pro-Syrian government resigned.