Video report by ITV News Political Correspondent Carl Dinnen
The British government and its western allies would be "unwilling" to enforce a no-fly zone over Syria, despite its vocal denunciations of airstrikes by the Assad regime and its Russian partners.
Dr Karin von Hippel, Royal United Services Institute, told ITV News that faced with Russia's sophisticated surface-to-air missiles and Syria's modern air defence system, there would be little appetite in Britain for imposing a no-fly zone.
"I don’t think the US nor the UK and other countries would provide the credible force of threat to back it up," Ms Von Hippel said.
"In order words, they have to be willing to shoot down Russian aircraft or Syrian regime aircraft if they’re violating Aleppo airspace."
Daily airstrikes over Syria resumed on Tuesday, mostly hitting the Bustan al-Qasr neighbourhood and causing casualties in the region.
Almost 300 people have been killed in airstrikes on residential neighbourhoods since September 22, when a joint US-Russian ceasefire ended.
Calls have been mounting for the imposition of a no-fly zone over the war-ravaged country, but experts warned that British aircraft could be shot down by Russia's air force.
Former Air Chief Marshal Sir Michael Graydon told ITV News: "If the Russians decided that they were going to block any attempt like this - they have some very capable aeroplanes - they are in a better position because they’re based in the country.
"They’ve got quite a lot of aeroplanes. We would need a pretty big armada to be effective."