A senior UAE official said on Saturday that his government had concerns about the Islamist affiliation of the forces that ousted Syrian president Bashar al-Assad.
"We hear some reasonable, rational language about unity, not imposing a system on all Syrians" from the country's new rulers, said Anwar Gargash, a presidential adviser in the United Arab Emirates, in remarks at the World Policy Conference in Abu Dhabi.
But "the nature of the new forces, the affiliation with the (Muslim) Brotherhood, the affiliation with Al-Qaeda, I think these are all indicators that are quite worrying," he said.
"We have to be optimistic on the one hand and help Syrians... but at the same time we can't ignore the region has seen episodes like this before, so we need to be on guard," added Gargash, citing the "brutal adventures" of the Islamic State group over the past decade in both Syria and Iraq.
Islamist-led rebel forces toppled Assad on Sunday following a lightning offensive that ended his family's five-decade rule and capped nearly 14 years of civil war.
The offensive was spearheaded by Hayat Tahrir al-Sham (HTS), which is rooted in Al-Qaeda's Syria branch and is designated a "terrorist" organisation by many Western governments, but has sought to moderate its rhetoric.
A transitional government installed by the HTS-led forces has insisted the rights of all Syrians will be protected, as will the rule of law.
As governments in the region and beyond eye the developments in Syria with some concern, Gargash said that the Arab world has "the responsibility to work not to repeat past mistakes".
The presidential adviser also condemned a wave of Israeli air strikes on strategic military sites in Syria.
"Using the crisis in Syria to structurally degrade Syrian capabilities might be seen a sensible thing from an Israeli practical point of view, but I think it's dumb politics," Gargash said.
"This is a new Syria that is creating itself," he said, arguing that Israel "should have sent a different message. I don't say a message of peace, because we are not there yet, but I think a different message."
The UAE normalised relations with Israel in 2020, one of only a handful of Arab governments to do so.