WASHINGTON – An audiotape that surfaced yesterday, purportedly from the leader of Al Qaeda in Iraq, Abu Musab al-Zarqawi, explicitly sanctions the murder of Muslim women and children if they stand in the way of Jihad.

“God ordered us to attack the infidels by all means,” the voice claiming to be Mr. Zarqawi said in the recording found in Cairo. The man went further, saying the slaying was justified, “even if armed infidels and unintended victims – women and children – are killed together.” One administration official here said that the recording was in the process of being authenticated by intelligence authorities, but that early analysis suggested the tape was real.

Mr. Zarqawi, according to an Associated Press report filed yesterday from Baghdad, urged terrorists in Syria to plan attacks in April when the elected Iraqi parliament was negotiating the formation of a government and there was a post-election lull in violence against Iraqi civilians. The newswire cited a senior American military official as saying intelligence from the field suggested a high-level meeting in Syria took place. There, a decision was made to intensify the attacks. “The Syrian meeting, possibly attended by Abu Musab al-Zarqawi himself, has led to one of the bloodiest periods since the U.S.-led invasion two years ago,” the AP reported. Since April 28 when the new government was formed, nearly 500 Iraqis have been killed in terror attacks.

The Jordanian-born terror leader has referred to his organization as Al Qaeda in Iraq. Last year, the American military released a letter Mr. Zarqawi drafted to the leadership of Al Qaeda expressing his desire to foment a civil war between Iraq’s Shiite population and its Sunni Muslim minority. In the last month, Iraqi military officials have said that they have apprehended lieutenants of Mr. Zarqawi.

At the Pentagon yesterday, the chairman of the Joint Chiefs of Staff, General Richard Myers, denounced the new message from Mr. Zarqawi. He said, “What he says is, it’s okay for Muslims to kill Muslims, and not just any Muslims but innocents, men, women, and children. And that’s what he’s been doing.”

The tape surfaced after senior administration officials chastised Syria for opening its border with Iraq to the flow of suicide bombers and jihadists. On her way home from Iraq earlier this week, Secretary of State Rice said Syria’s “unwillingness to deal with the crossings of their border into Iraq is frustrating the will of the Iraqi people.” She added that America has asked Syria’s neighbors to pressure the regime there to do more to crack down on the flow of foreign terrorists.

A state-run newspaper in Syria yesterday accused Ms. Rice of lying, saying that the Syrian regime has worked to stabilize the web of roads connecting Syria and Iraq that have for centuries served as smuggling routes. “These accusations are baseless,” the paper, Tishrin, wrote in an editorial.

The accusations, however, are not new. The American embassy in Damascus before the war cabled the State Department claiming that Hezbollah leaders and other terrorist groups were recruiting volunteer fighters in fairgrounds outside Damascus to serve in Iraq. The Pentagon during the initial hostilities of Operation Iraqi Freedom publicly urged Syria to stop busloads of terrorists from crossing into Iraq. More recently, the Treasury Department has issued internal reports claiming that large swaths of the Ba’athist elements of the insurgency are funded by Syrian banks.

It was not until November that the State Department officially began a sustained public berating of Syrian bad behavior. Syria and Iran were invited in November to a conference on the insurgency in Cairo that was heavily promoted by Ms. Rice’s predecessor, Colin Powell, as a summit to negotiate a regional policy on the widespread terror campaign in Iraq. The British government in September arranged for – but is yet to have followed through on – the sale of night-vision goggles and other border-control technology to better secure the border between Iraq and Syria.

“The border between Syria and Iraq is invisible to the insurgents. The campaign of insurgency is based on alliances that cross these borders. These bonds go back hundreds of years,” the president of the reform party of Syria, Farid Ghadry, said yesterday. “It is no surprise that Zarqawi has been able to get support from terrorists with the knowledge and approval of the Syrian government.” Mr. Ghadry’s organization will open political offices next month in Syria, and has pressed the Assad regime to hold free elections.