RAF Tornados will continue strikes against Islamic State until 2017

The UK is to extend air strikes by RAF Tornados against Islamic State in Iraq by a year, the defence secretary has said, arguing that the aircraft had “proved their worth” in the air campaign.

Michael Fallon has said a squadron of Tornado GR4 fighter bombers will continue in service until March 2017, despite originally having been due to be disbanded last March and replaced with a squadron of Typhoon air defence fighters.

Following the first UK air strikes against Isis last September, David Cameron announced that they would carry on for an extra 12 months so they could continue in their specialist ground-attack role.

The head of the armed forces, Gen Sir Nicholas Houghton, warned last month that the RAF was operating at “the very limits of fast jet availability and capacity”. His comments came as Tornado bombing missions against Isis were temporarily halted after two missiles fell off one of the ageing aircraft on landing.

In July, defence analysis group IHS Jane’s said the RAF could be left with just 127 combat jets by the end of the decade – its fewest number of fighter planes since 1918 – as 87 Tornados and 53 Typhoon jets were due to be retired.

During a visit to Baghdad, Fallon said the Tornado squadrons had “proved their worth in the air campaign because of the precision weapons that they have and because of the reconnaissance and surveillance that they carry out when they’re not striking”.

He told the BBC Radio 4’s Today programme: “They’ve carried out something like 30% of all the surveillance and intelligence gathering missions. The Americans and other allies have particularly valued the contribution of the Tornado, and that’s why we’re continuing the Tornado squadron for another year.”

The decision was welcomed by the head of the RAF, Air Chief Marshal Sir Andrew Pulford, who said it was “clear that the requirement for fast jet precision strike and intelligence gathering” showed no sign of diminishing.

Cameron and Fallon have made it clear they are considering extending the military air campaign to Syria after the Tunisian beach massacre in June, in which 38 people were killed, including 30 Britons.

In 2013, the House of Commons voted against military action in Syria and parliamentary authorisation has so far only been given to UK air strikes against Isis in neighbouring Iraq, but a freedom of information request by the campaign group Reprieve revealed that British pilots, embedded with coalition forces, had taken part in bombings of Isis targets in Syria.

Fallon dismissed the suggestion that more aircraft would be needed if UK forces began airstrikes over Syria. “We’re already flying six days a week, pairs of aircraft each day and each night,” he said. “We’re playing the second part behind the United States in the number if missions being flown.

“It isn’t the number of aircraft, it’s where they are. And what the rest of the coalition – there are some 16 other countries involved in strikes against Isil – would welcome is certainly the participation of Tornado in strikes against Isil headquarters in northern Syria, but to do that we need the authority of parliament.”

In his July budget, George Osborne pledged to increase the defence budget as part of a commitment to spend at least 2% of national income on the armed forces until 2020. But Labour said the chancellor had not announced any new defence spending and had instead included money for intelligence-gathering in its calculations.