British combat pilots covertly embedded in American and Canadian coalition forces have been bombing targets in Syria without democratic sanction, a Freedom of Information (FoI) request has revealed.

Ministry of Defence (MoD) documents obtained by UK human rights group Reprieve on Thursday indicate that British air forces have been involved in military airstrikes over Syria for quite some time.

No10 spokeswoman on Syria bombing: "PM was aware that UK pilots were involved and what they were doing." — steve hawkes (@steve_hawkes) July 17, 2015

This revelation makes “current debate over whether Britain should carry out such strikes somewhat obsolete,” staff lawyer at Reprieve Jennifer Gibson said in a statement on Friday.

“It is alarming that Parliament and the public have been kept in the dark about this for so long,” she added.

An extract from the MoD response to Reprieve’s FOI request says: “UK military personnel embedded with the USA, French and Canadian armed forces have been authorized to deploy with their units to participate in coalition operations against ISIL [Islamic State].

“These personnel include pilots flying ISR and Strike missions against ISIL targets using the equipment of those units. Of these three nations only the USA and Canada are operating in Syrian airspace.”

Govt to launch cross party review into future of freedom of information act. Not ideal day after an FoI confirms UK pilots bombing in Syria — Patrick Wintour (@patrickwintour) July 17, 2015

The admission says that “UK Embeds operate as if they were the host nation’s personnel, under that nation’s chain of command,” bringing into question the legal basis for UK personnel’s apparently long-running involvement in airstrikes on Syria.

The revelations have created immediate dissent in the government, with Tory MP John Barron telling the BBC that Parliament had said “no to military intervention."

"Those troops or individuals should be withdrawn from the embedded program whilst this vote holds sway, while it stills hold authority, until we vote again.”

Convenor of Stop the War Coalition Lindsey German slammed the government’s covert military tactics.

“Parliament voted against bombing Syria two years ago. Now we find that the government ignored this and allowed British pilots to bomb under US command,” she told RT on Friday.

“This was a political not a military decision and shows the contempt our Prime Minister has for democratic decisions. This should stop now and we should oppose all further attempts to bomb Syria.”

While the UK has been involved in airstrikes against Islamic State (IS, formerly ISIS/ISIL) in Iraq since September 2014, UK MPs voted against military intervention in crisis-ridden Syria in August 2013. The outcome of the vote caused considerable embarrassment to Prime Minister David Cameron, who openly backed the move.

Responding to a question put by then-Labour Leader Ed Miliband at the time, Cameron vowed to seek another vote before extending combat operations to Syria.

On Friday, Downing Street’s official spokeswoman confirmed to the Guardian that the PM knew that UK pilots had been involved in combat operations in Syria since September 2014.

However, she claimed that they were operating under a US chain of command.

The spokeswoman said that up to a dozen pilots may have been involved in the operations, with sources adding that the personnel were operating the F-18 Super Hornet aircraft from a US aircraft carrier in the Gulf.

In a formal statement, the MoD said that the UK has a “long-standing embed program with allies, where small numbers of UK personnel act under the command of host nations."

Following June’s terror massacre in Tunisia which left 30 British tourists dead, senior political and military figures in the UK have once again started to push for airstrikes in Syria.

In 2013, Britain’s proposed military intervention in the war-torn state was aimed at overthrowing Syrian President Bashar Assad. Recent debate on UK airstrikes in the region has focused on obliterating IS militants operating there.

UK Defence Secretary Michael Fallon recently said the extension of British bombing operations in Syria was a logical move. Speaking at an airpower conference held in London on Thursday, he compared Islamic State to Nazi fascists from the 1940s.

The Labour party has called for an explanation from the MoD by Monday morning.