UNITED NATIONS – The United Nations-appointed investigator, Detlev Mehlis, has asked to interview Syria’s foreign minister, Farouk al-Sharaa, as a witness, a source familiar with the Rafik Hariri assassinaton probe told The New York Sun yesterday.

Mr. Mehlis has also demanded to conduct interviews in Lebanon with six Syrian suspected in the killing, including President al-Assad’s brother-in-law, Assef Shawkat. The source, who declined to be identified citing sensitivities in the negotiations, said that a Syrian refusal to accept any of Mr. Mehlis’s demands could soon lead to a major crisis and possible declaration of Syrian non-compliance by the Security Council.

A much-publicized speech by Mr. al-Assad yesterday was characterized as “appalling” by Bush administration officials, who also said it pointed to noncompliance. The speech assailed Israel and the American role in the Middle East, and used threatening language toward the elected Lebanese prime minister, Fouad Siniora.

Mr. Mehlis is leading the investigation into the February Hariri assassination at the request of the Security Council. The council recently passed a resolution demanding complete Syrian cooperation with the investigation and threatening unspecified sanctions in case of a failure to comply.

“I don’t think this constitutes cooperation,” Secretary of State Rice told reporters yesterday on her way to Europe, referring to the al-Assad speech. Syria is “expected to answer affirmatively, positively, yes, to whatever Mehlis needs to complete his investigation. And I do not believe that the U.N. Security Council resolution contemplated the Syrians negotiating how they would say yes.”

Syria’s U.N. ambassador, Fayssal Mekdad, said yesterday that “there are no limits on our cooperation.” Asked about Mr. Mehlis’s requests to interview Syrian officials, he said, according to Bloomberg News, “We would accept any place he finds suitable, under a U.N. flag, in a third country,” except Beirut.

Mr. Mehlis, who departed Lebanon for Europe yesterday, wants the interviews to be conducted at his Beirut headquarters, in proximity to the crime scene and away from Damascus, where his investigators have little control over the proceedings. “A change of venue is out of the question,” he said according to press reports in Lebanon.

“We will not allow any measure that will harm the security or the stability of Syria,” Mr. al-Assad said in his rare televised speech yesterday at Damascus University. “President Bashar will not be the one to bow the head before anybody in this world,” he said, adding, “No matter what we do and how much we cooperate, the result after a month will be that ‘Syria did not cooperate’… but we have to do our duty.”

The growing international pressure on Syria, led by France and America, is seen by the Damascus Baathists as an affront to Arab traditions. “There are efforts on the political front to change the cultural face of the region and to draw a new map,” Mr. al-Assad said in his speech. “The Israeli factor was present in all of these attempts.”

The Security Council has demanded that Syria stop interfering in Lebanon’s affairs, but Mr. al-Assad accused Prime Minister Siniora, a close associate of the late Hariri, of turning the country into a platform for enemies of Damascus. “Lebanon has become a passageway, a factory, and a financier of these conspiracies,” he said.

“We saw the speech. We think it is appalling,” a State Department spokesman, Adam Ereli, said. “It shows that the regime of President al-Assad just doesn’t get it and doesn’t understand where the rest of the international community is.” America’s U.N. ambassador, John Bolton, told the Sun that speeches matter less than what Syria does to cooperate with the council. “The clock is ticking,” he said.