CAIRO — Al-Qaida’s central leadership broke with one of its most powerful branch commanders, blaming him for bloody infighting among Islamic factions in Syria, in an apparent attempt to impose control over militant factions in the country’s civil war.

More broadly, the announcement issued Monday on Islamic militant websites appeared to be a move by al-Qaida’s leader Ayman al-Zawahri to reassert the terror network’s prominence in the jihad movement across the Middle East amid the mushrooming of multiple extremist groups during the upheaval of the past three years.

The dispute between the two groups had been building the past year between al-Qaida’s central leadership and the faction known as the Islamic State of Iraq and the Levant. The head of al-Qaida’s branch in Iraq, Abu Bakr al-Baghdadi, formed the Islamic State last spring to expand his operations into neighboring Syria, defying direct orders by al-Zawahri not to do so and to stick to operations within Iraq. Al-Zawahri named a different group, the Nusra Front, as al-Qaida’s branch in Syria.

Now, the break is likely to spark a competition for resources and fighters between the two sides in what has become a civil war within a civil war as Syria’s rebels fight against President Bashar Assad. The test for al-Zawahri’s influence will be whether his decision leads to fighters quitting the Islamic State.

In a conflict that has seen atrocities by all sides, the Islamic State has been particularly vicious. It is believed to be dominated by thousands of non-Syrian jihadi fighters, seen by others in the rebellion as more concerned with venting sectarian hatreds and creating a transnational Islamic caliphate than with toppling Assad. Since its creation, it has taken over swaths of territory in northern and eastern Syria, often imposing Shariah law penalties harsher than other Islamic-minded groups.

Its fighters have beheaded captured government fighters, carried out some of the deadliest massacres against members of the pro-Assad Shiite and Alawite minorities and kidnapped anti-Assad activists, journalists and civilians seen as critical of its rule.

It has increasingly clashed with other factions, particularly an umbrella group of Syrian rebels called the Islamic Front, which accuses it of trying to hijack the campaign to oust Assad. Even the group’s name, Islamic State of Iraq and Levant, was seen as a declaration that the group was the only real Islamic movement in the country.

Those frictions erupted into outright warfare in January. Since Jan. 3, more than 1,700 people have been killed in fighting between Islamic State and other factions, according to the London-based Syrian Observatory for Human Rights. On Saturday, the Islamic State killed two senior commanders from factions that make up the Islamic Front, one of them in a giant suicide bombing that killed more than two dozen people near the northern city of Aleppo.

At the same time, the Islamic State’s leader al-Baghdadi has brought his group back to the forefront in his homeland Iraq. The past month, his fighters rose up and virtually took over main cities of Iraq’s western Anbar province, and they continue to hold out against sieges by Iraqi government troops. His group has sought to present itself as the voice of that country’s Sunni minority against the Shiite-led government.

That has made al-Baghdadi a powerful force in the jihadi movement. Notably, the main militant group in Egypt, Ansar Beit al-Maqdis, saluted the Islamic State of Iraq and Levant in an audiotape released in January — a reflection of its influence.

With Monday’s statement, al-Qaida appeared intent on undercutting al-Baghdadi’s allure by making clear he was not supported by the central leadership.

Al-Qaida’s general command announced it has “no connection” with the Islamic State, underlined that the group “is not a branch of the al-Qaida organization,” and said al-Qaida “is not responsible for its actions.”

Al-Qaida did not condone the group’s creation “and in fact ordered it to stop,” the statement said.

It also condemned the infighting among Islamic groups, saying, “We distance ourselves from the sedition taking place among the mujahedeen factions.”

The authenticity of the statement could not independently be verified but it was posted on websites commonly used by al-Qaida.

Charles Lister of the Brookings Doha Center said the al-Qaida statement reflected its “attempt to definitively re-assert some level of authority over the jihad in Syria.”

However, he doubted the Islamic State would back down, saying its attacks on rival factions “have been aimed at weakening opponents’ key strategic strongpoints and command and control.”

A spokesman for the Islamic Front vowed that the umbrella group would continue battling the Islamic State. Capt. Islam Alloush said al-Qaida’s announcement came late but praised it for isolating the Islamic State. “This faction is without cover or cosponsor. It has been totally stripped after al-Qaida and the people abandoned it,” Alloush told The Associated Press.

The dispute points to wider tensions within the jihadi movement, with implications for the leadership of al-Zawahri, who succeeded Osama bin Laden as head of al-Qaida.

Al-Qaida has official branches in North Africa, Yemen, Syria, Somalia and — until now — Iraq. But numerous militant groups sprung up in the turmoil across the Middle East since the Arab Spring uprisings began in late 2010. Many of them are inspired by al-Qaida’s ideology and show it a degree of respect, but the leadership has no control over them.

In that context, al-Baghdadi represents competition. Several prominent jihadi ideologues had lined up in support of his Islamic State of Iraq and the Levant, particularly Abu Mundhir al-Shanqiti, an influential sheik believed to be from Mauretania.

The divisions were immediately clear as participants in Islamic militant websites quickly weighed on Monday’s announcement. The participants are registered by username pseudonyms but their views are believed to reflect the wide variety of sentiments within the jihadi movement.

Some denounced the Islamic State for defying the leadership and attacking fellow mujahedeen.

But Islamic State supporters angrily said al-Qaida’s leadership was turning its back on a powerful group fighting for the cause.

“The al-Qaida that we loved and prayed to God to make victorious died with the death of Sheik Osama (bin Laden),” one by the username Muslim2000 wrote. “God as my witness, al-Qaida did not do right by this mujahed group. Instead, it stood with its enemies.”