BORIS Johnson was yesterday pressed to explain why if bombs can be dropped on eastern Aleppo then “why not bread/” as MPs highlighted the suffering of civilians in the last remaining opposition-held enclave of the Syrian city.

Patrick Grady, the SNP’s international development spokesman, spoke about “the unimaginable horror of life in the city” as the dire humanitarian situation was laid bare in a two-hour debate.

“Once again, we are in the chamber debating as civilians in Aleppo are literally being shot on the spot, according to some of the harrowing reports,” Grady said.

“Let us be clear. We have failed the people of Aleppo, who are trapped in the ruins of their homes sending their final messages in the face of indiscriminate and unrelenting bombardment by the Syrian regime.”

He added: “If we can drop bombs in Syria, we should be able to drop bread and the Government has repeatedly said this would be an option of last resort.

“When is that last resort going to be reached? No food has been delivered to eastern Aleppo for seven months.

“British bombs have achieved nothing and it is beyond last resort for the people of Aleppo.”

Fellow Scottish MPs Tommy Sheppard and Stewart McDonald also took to the floor, with the former urging the Government to “show world leadership” while the latter asked for sanctions to be considered against Russia which is backing the military action by President Bashar al-Assad’s forces.

Responding to calls from a host of MPs across all parties, Johnson said aid drops over Syria were too great a risk under current conditions, warning transport aircraft would be “sitting ducks”.

The Foreign Secretary said Russia had deployed its most advanced jet fighters and surface-to-air missiles inside Syria, arguing this made it impossible for Britain to carry out aid drops without Russian permission.

He also accused Russia of blocking the evacuation of those who are injured and medical staff from leaving areas of Aleppo.

Replying to the emergency debate, Johnson told MPs: “As things stand, we’d be risking the lives of our aircrew if we were to try to drop supplies into eastern Aleppo.”

Johnson criticised Russia, and later China, for blocking draft resolutions tabled at the UN designed to ease the suffering in Aleppo.

The Russian-backed Syrian military announced yesterday it has gained control of 99 per cent of the former opposition enclave of east Aleppo and it looks close to retaking the city.

United Nations secretary general Ban Ki-moon has raised concerns over reports of “atrocities against a large number of civilians, including women and children”.

Labour MP Alison McGovern pressed for details on what action Theresa May will call for when she meets with European leaders this week.

During the debate former chancellor George Osborne warned MPs they were “deceiving” themselves if they believe they do not bear some of the responsibility for the “terrible tragedy”.

The Tory MP said the situation in Syria was the result of “a vacuum of western leadership” as he suggested countries such as the UK were now beginning to learn the price of non-intervention abroad after MPs voted against military action in 2013.

Opening the emergency debate, Conservative former minister Andrew Mitchell said Britain was “complicit” in the suffering.

He said: “This country, along with the entire international community, 10 years ago embraced the responsibility to protect, a doctrine which said that nation states will not allow the Srebrenicas, the Rwandas and other appalling events, including in Darfur, to take place again.

“This responsibility to protect was signed up to at great fanfare and embraced by all the international community, great and small.

“Yet here we are today witnessing, complicit, in what is happening to tens of thousands of Syrians in Aleppo.”

Shadow foreign secretary Emily Thornberry urged the Government to consider using drones or GPS-guided parachutes to drop humanitarian aid into the city.

She also suggested the international community should feel “deep sorrow” as it reflects on what has happened in Aleppo.

At the end of the debate, Mitchell raised the prospect of a fresh vote on military action, which Commons Speaker John Bercow said was possible for the Government if it so wished.