Hezbollah leader Hassan Nasrallah said on Tuesday that his group would target al Qaeda militants across the border in Syria to ensure that the “unacceptable threat” to Lebanon’s security is wiped out. The Shiite Hezbollah group, which is an ally of Syrian President Bashar Assad, has already sent several fighters to help the regime combat Sunni rebels, including members of Jabhat al-Nusra and the Islamic State group.

“The [Lebanese] state is not able to address this issue ... so we will proceed with the necessary treatment and assume the responsibility and consequences,” Nasrallah reportedly said on Tuesday, referring to the presence of al-Nusra militants in the Qalamoun Mountain region along Lebanon’s border with Syria.

“This issue needs radical treatment. We are talking about a real aggression that exists and is present,” he added. However, he reportedly declined to reveal when the operation would begin. “There are preparations, and people are seeing that and speculating about it. But we haven't announced anything official ... and even when we start, we will not issue a statement,” he said in a televised address.

Most of the territory captured in the Qalamoun Mountains by rebel forces was reclaimed last year by Syrian regime forces, which are backed by Hezbollah fighters. However, several fighters, including militants of Jabhat al-Nusra and ISIS are still believed to be entrenched in the region, and have launched sporadic attacks on Lebanon.

Hezbollah’s support to Assad has also created sectarian divisions in the Lebanese society. The country, which has an almost equal proportion of Shias and Sunnis, has witnessed sporadic incidents of sectarian violence since the beginning of the Syrian civil war in 2011. The Sunnis in the country support the Syrian rebels, while the Shias support Assad.

“This is not the battle of the Syrian people alone,” Nasrallah reportedly said. “I tell our dear people in Syria that we were with you and will continue to be by your side -- no matter what the developments are.”