Syria's new rulers Friday denounced an Israeli air strike near the presidential palace as a "dangerous escalation".
The dawn strike came hours after senior Druze clerics and armed factions reaffirmed their loyalty to Damascus and rejected any call for secession.
They also urged the authorities to appoint local officials to government posts in the Druze heartland in Sweida province.
The statement followed sectarian clashes between Druze fighters and Syrian forces, including government-affiliated groups.
More than 100 people were killed in Jaramana and Sahnaya near Damascus and in Sweida, war monitor the Syrian Observatory for Human Rights said.
Friday's explosion from the Presidential Palace area was heard across Damascus.
Syria's presidency called the strike "a dangerous escalation against state institutions", and accused Israel of destabilising the country.
UN Secretary-General Antonio Guterres condemned the Israeli strike as a violation of Syria's sovereignty, which he said Israel must respect along with "its unity, its territorial integrity and its independence", his spokesman said.
After this week's sectarian clashes a de-escalation deal was agreed between Druze representatives and the government, prompting troop deployments in Sahnaya and tighter security around Jaramana.
Syrian officials said the agreement also included the immediate surrender of heavy weapons.
An AFP photographer saw troops taking over checkpoints from Druze gunmen in Jaramana, although no handover of weapons was witnessed.
A German foreign ministry statement said "Syria must not become the venue for regional tensions to be played out".
Israel has attacked hundreds of military sites since longtime president Bashar al-Assad was deposed in December. It has also sent troops into the demilitarised buffer zone that used to separate Israeli and Syrian forces on the Golan Heights.
On Wednesday, Israel launched strikes near Damascus and threatened more if violence against the Druze continued.
The unrest inside Syria was sparked by the circulation of an audio recording attributed to a Druze citizen and deemed blasphemous.
Syria's government said "outlaw groups" were behind the violence.
"The situation is calm, but we are scared. Everyone is terrified," 35-year-old housewife Arij told AFP, adding that many Christians and Druze "have fled to Damascus".
State news agency SANA reported that security forces were being sent to Sweida to "maintain security".
This aerial photo shows the Presidential Palace in Damascus' Mount Qasyoun. Israel bombed an area near the palace early Friday.
