AMMAN, Jordan (AP) — The Syrian military on Sunday launched an offensive to retake a strategic rebel-held town near the Lebanese border, a government official said, as activists reported that regime airstrikes and shelling of the town have killed at least 16 people, including opposition fighters.

The western Syrian town of Qusair, home to about 20,000 residents, has been besieged for weeks by government troops. According to opposition activists, members of the Lebanese militant Hezbollah group were fighting alongside President Bashar Assad’s forces in the area. Hezbollah has been a staunch Assad ally throughout Syria’s conflict.

The Britain-based Syrian Observatory for Human Rights said 16 people, including rebel fighters, were killed before noon in Qusair but that the death toll was expected to rise as fierce fighting is underway and the military’s operation intensifies.

Speaking over the telephone, a government official in Qusair said government forces have encircled the town, beefing up three offensive positions around it while leaving one “safe passage for fleeing civilians and the armed terrorists who want to surrender.”

“The offensive to liberate Qusair has begun,” the official told The Associated Press. He would not elaborate further, speaking on condition of anonymity because he was not authorized to talk to the media.

Officials in Damascus were not immediately reachable for comment on the offensive. Assad’s government and loyalists deny there is a civil war in the country but blame the conflict on “terrorists” — a term they use for rebel fighters — backed by a foreign conspiracy.

Qusair, close to the border with Lebanon and 164 kilometers (102 miles) northwest of the Syrian capital, is strategically important because it also links Damascus with Syria’s Western coast, where regime loyalists are concentrated. This includes Alawites, followers of a Shiite offshoot to which the Assad family belongs. The rebellion against Assad is largely driven by Syria’s majority Sunnis.

The push on Qusair may be an attempt by the regime to regain as much ground as possible before agreeing to any negotiations with the opposition in the wake of a recent U.S-Russian effort to get Assad and his opponents to negotiate an end to the country’s civil war. Previous attempts to solve the conflict peacefully have failed.

The U.S.-Russian plan, similar to one set out last year in Geneva, calls for talks on a transition government and an open-ended cease-fire.

More than 70,000 people have been killed and several million displaced since the uprising against Assad erupted in March 2011 and escalated into a civil war.

On Saturday, Assad said in a newspaper interview that he won’t step down before elections and that the United States has no right to interfere in his country’s politics.

Assad’s comments to the Argentine newspaper Clarin were the first about his political future since Washington and Moscow agreed earlier this month to try to bring the regime and the opposition to an international conference for talks about a peaceful resolution to the conflict. The U.S. and Russia have backed opposite sides in the conflict, but appear to have found common ground in the diplomatic push.

The White House and the Kremlin envision holding the meeting next month, but no date has been set. Neither Assad nor the Syrian National Coalition, the main Western-backed opposition coalition group, has made a firm commitment to attend.

In the interview, Assad seemed to play down the importance of such a conference, saying a decision on Syria’s future is up to the Syrian people, not the U.S. He also said a decision on his political future must be made in elections, and not during such a conference.

“We said from the beginning that any decisions having to do with reform in Syria or any political doing is a local Syrian decision,” Assad said. “Neither the U.S nor any other state is allowed to intervene in it. This issue is dealt with in Syria.”

“That’s why this possibility is determined by the Syrian people themselves; you go to the elections, you nominate yourself, there’s a possibility you win and a possibility you don’t,” Assad added, hinting he might seek another term.

Copyright 2013 The Associated Press.