In his first televised statement after powerful Israeli air strikes on Damascus on Wednesday, Sharaa addressed Druze citizens, saying "we reject any attempt to drag you into hands of an external party".
"We are not among those who fear the war. We have spent our lives facing challenges and defending our people, but we have put the interests of the Syrians before chaos and destruction," he said on Thursday.
He added that the Syrian people are not afraid of war and are ready to fight if their dignity is threatened.
Israel's airstrikes blew up part of Syria's defence ministry and hit near the presidential palace as it vowed to destroy government forces attacking Druze in southern Syria and demanded they withdraw.
The attacks marked a significant Israeli escalation against Sharaa's Islamist-led administration.
They came despite his warming ties with the US and his administration's evolving security contacts with Israel.
Describing Syria's new rulers as barely disguised jihadists, Israel has said it will not let them move forces into southern Syria and vowed to shield the area's Druze community from attack, encouraged by calls from Israel's own Druze minority.
The US said the fighting would stop soon.
"We have engaged all the parties involved in the clashes in Syria. We have agreed on specific steps that will bring this troubling and horrifying situation to an end tonight," Secretary of State Marco Rubio said on social media.
The United Nations Security Council will meet on Thursday to address the conflict, diplomats said.
"The council must condemn the barbaric crimes committed against innocent civilians on Syrian soil," said Israel's ambassador to the UN, Danny Danon.
"Israel will continue to act resolutely against any terrorist threat on its borders, anywhere and at any time."
The Syrian Network for Human Rights said 169 people had been killed in this week's violence. Security sources put the toll at 300. Reuters could not independently verify the tolls.
Reuters reporters heard warplanes swoop low over the capital Damascus and unleash a series of massive strikes on Wednesday afternoon. Columns of smoke rose from the area near the defence ministry. A section of the building was destroyed, the ground strewn with rubble.
An Israeli military official said the entrance to the military headquarters in Damascus was struck, along with a military target near the presidential palace. The official said Syrian forces were not acting to prevent attacks on Druze and were part of the problem.
"We will not allow southern Syria to become a terror stronghold," said Eyal Zamir, Israel's military chief of staff.
Sharaa faces challenges to stitch Syria back together in the face of deep misgivings from groups that fear Islamist rule. In March, mass killings of members of the Alawite minority exacerbated the mistrust.
Druze, followers of a religion that is an offshoot of Islam, are spread between Syria, Lebanon and Israel.
Israeli Prime Minister Benjamin Netanyahu said the Israeli military was working to save the Druze and urged Israeli Druze citizens not to cross the border.
with Reuters
