WASHINGTON — Vice President Joseph R. Biden Jr. has one more stop on what has become a Middle East apology tour in the wake of his impolitic answer to a Harvard student’s question: Saudi Arabia.
After apologizing to officials from Turkey and the United Arab Emirates over the weekend, Mr. Biden is trying to connect with Saudi leaders, a senior official said, to clarify that he did not mean to suggest that Saudi Arabia backed Al Qaeda or other extremist groups in Syria.
The vice president’s troubles began Thursday when he declared, in a question-and-answer session at the John F. Kennedy School of Government, that the biggest problem the United States faced in dealing with Syria and the rise of the Islamic State was America’s allies in the region.
Turkey, Mr. Biden said, has admitted allowing foreign fighters to cross into Syria, while Turkey, the United Arab Emirates and Saudi Arabia funneled weapons and other aid to Syrian rebels that ended up in the hands of Al Nusra, Al Qaeda and other extremist groups.
The White House expressed relief on Monday over Mr. Biden’s apologies, with the press secretary, Josh Earnest, noting that “the vice president is somebody who has enough character to admit when he’s made a mistake.” But asked repeatedly about the substance of his remarks, Mr. Earnest did not say the vice president was wrong.
In fact, neither of Mr. Biden’s claims is inaccurate. The United States has been pressing the Turkish government for months to seal off its border to prevent would-be jihadists from using Turkey as a transit route to join the ranks of the Islamic State. And experts say aid from the Persian Gulf monarchies has wound up with extremist groups in Syria.
President Obama made a similar point in August about Syria’s Arab neighbors fueling extremist organizations in their zeal to oust President Bashar al-Assad, though he did not name the culprits.
“There are factual mistakes, and then there are political mistakes,” said Andrew J. Tabler, an expert on Syria at the Washington Institute for Near East Policy. “This is a political mistake.”
The timing of Mr. Biden’s remarks was particularly awkward, given the fragility of the Sunni Arab coalition that Mr. Obama is trying to build to confront the Islamic State.
The Obama administration is engaged in tortuous negotiations with Turkey about the scale and nature of its participation in the military campaign against the Islamic State. And while Mr. Obama lined up Saudi Arabia, the United Arab Emirates, Jordan and Qatar to take part in airstrikes against the militants in Syria, preserving the coalition over a prolonged campaign that could require Arab ground troops will be challenging.
“The fact that he called the leaders of these, or at least senior officials, in both of these countries to apologize is an indication that he himself wishes he had said it a little bit differently,” Mr. Earnest said.
Mr. Biden’s gaffe overshadowed what was meant as a major foreign policy address, in which the vice president sought to put the multiple upheavals in the world — the Islamic State, the Ebola outbreak and the confrontation with Russia over Ukraine — into a broader context.
The vice president just hired a new national security adviser, Colin H. Kahl, a former Pentagon official and a Georgetown scholar who specializes in Iran. Mr. Kahl, who worked as a foreign policy adviser to the 2012 Obama campaign, had a major hand in the speech.
Several officials said Mr. Biden’s contrite phone calls to President Recep Tayyip Erdogan of Turkey and the crown prince of Abu Dhabi, Mohammed bin Zayed, had cleared the air. Mr. Biden takes particular pride in his relationship with the prickly Mr. Erdogan.
In December 2011, he was granted a two-hour session with Mr. Erdogan, then the prime minister, when he was recuperating at his private residence from a medical procedure. Mr. Biden and his aides put on slippers and were introduced by Mr. Erdogan to his son, daughter and son-in-law.
In a recent conversation, Mr. Biden said, the Turkish leader confided, “You were right — we let too many people through” and was now trying to seal its border. Mr. Erdogan denied saying that and told reporters, “If Mr. Biden has said such a thing at Harvard, he needs to apologize.”
“Foreign fighters never crossed into Syria from our country,” he said. “They would cross into Syria from Turkey on tourist passports, but nobody can claim that they have crossed with arms.”
When Mr. Biden speaks with Saudi officials, he may also have to deal with a comment he made later in the session, comparing the decision of the United States to work with Saudi Arabia to the American decision to ally with Stalin in fighting Hitler during World War II.
“I’m being a little facetious,” he said. “All generalizations are false, including this one I’m about to make.”
Mr. Biden’s comments came at the end of a trouble-prone period during which he has apologized to Jewish groups for using the word “shylock” and raised eyebrows for praising a former Senate colleague — Robert Packwood, an Oregon Republican who resigned in 1995 after multiple accusations of sexual harassment — at a Democratic women’s conference.