Ben Wallace said the decline of Isis – after becoming “the latest terrorist boy band” – had created renewed space for the perpetrators of the 9/11 atrocity in 2001.

He revealed the government was ploughing £25m into a research programme to protect planes from new methods of explosion and “insider threats”.

And he warned: “The aviation threat is real. Aviation is still a blue riband event for these terrorists.

“Al-Qaeda are resurgent. They have reorganised. They are pushing more and more plots towards Europe and have become familiar with new methods and still aspire to aviation attacks.”

Speaking to The Sunday Times, Mr Wallace said improvements in airport security meant terrorists were less likely to smuggle explosive through terminal security systems:

“They have explored other ways of getting bombs on planes. We’ve talked publicly about an insider threat issue. If you can’t get in the front door, you’re going to try to get in the back door,” the minister said.

He pointed to a failed attack against an Australian airliner in July 2017 as evidence that aviation targets are still a favourite with terrorists: “In 2019, we should be alert to al-Qaeda. They are re-energising some previous links and support and their ambition towards aviation is real. We saw in Australia that terrorists do what works and they don’t give up.”

“Al-Qaeda sat quietly in the corner and tried to work out what the 21st century looked like, while Isis became the latest terrorist boy band, but they have not gone away.

“They have reorganised. You’re seeing al-Qaeda appear in areas we thought were dormant.”

Al-Qaeda and its affiliates were now active in Syria, Afghanistan, Yemen, Libya and other countries in the Middle East under a new generation of leaders, although Ayman al-Zawahiri, Osama bin Laden‘s former deputy, was still its spiritual head.

The Sunday Times also reports that British intelligence chiefs are concerned that Donald Trump’s decision to withdraw US troops from Syria will create a new safe haven for Islamists to launch attacks on the west.

The UK found out about his decision only when the US president tweeted it on Wednesday.

The paper reports that security sources say sketches of drones designed to deliver bombs were discovered during a recent terrorist investigation in the UK.

British businesses have also been warned that Islamist terrorists are seeking to mount attacks using a drone armed with explosives or chemicals.

A threat assessment published by Pool Re, the government-backed terrorism reinsurer, states: “The vulnerability of airspace and the opportunity it provides to expand targets for an attack is increasingly recognised.”

The Independent

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