The defence secretary John Healey accused opposition politicians of deliberately undermining the UK’s relationship with Donald Trump, saying it was “unpatriotic” for MPs to seek to turn the US against Keir Starmer.

Healey, speaking to the Guardian at RAF Akrotiri in Cyprus, which was hit by a drone strike over the weekend, said he had been shocked at the way politicians like Nigel Farage had sought to “undermine” the UK’s relationship with the US.

The Conservatives and Reform UK have criticised the British decision not to allow the US to use UK bases for offensive strikes against Iranian targets, though they will be used to help defend UK interests and allies in the region from Iranian retaliatory attacks.

But Healey said he had been shocked by the extent to which senior MPs had sought to curry favour with the US president by undermining the position of the UK government – not just on the Iran attacks but also over the Chagos Islands deal.

Kemi Badenoch, the Tory leader, and Farage, have both praised Trump for his opposition – albeit fluctuating – to the government’s Chagos plan, which the US president criticised when apparently frustrated with the UK over other issues.

“For an elected British politician from the House of Commons, from Reform or from the Conservatives, to be going over to America … calling on President Trump to disown the deal we’d agreed and worked through to protect for the next 100 years our sovereign base and ability to operate out of Diego Garcia – it is unpatriotic, it undermines Britain and it is not the sort of leadership that British people should expect from elected politicians,” said Healey.

“It looks like to me their intent is to undermine the British relationship with the US. That seems to be their intent, unpatriotic, unacceptable and not what people should expect of people who are elected to speak up in parliament and represent this country.”

British allies in the Gulf and Cyprus have criticised the government for not doing enough to protect the region, and UK citizens stuck there, from Iranian missile strikes.

Healey travelled to Cyprus to calm the diplomatic fallout over a drone that evaded detection and hit a hangar at RAF Akrotiri containing spy planes, with little damage, which prompted fury from local ministers.

The Cypriot high commissioner in the UK, Kyriacos Kouros, said the country was “disappointed” with British failures to warn people on the island of the impending strike.

Healey met with the Cypriot defence minister, Vasilis Palmas, to discuss how the UK was reinforcing air defences. An additional 400 UK personnel are supporting air defence activities across the UK’s bases in Cyprus.

After Keir Starmer was unable to say whether he was confident Trump had a plan for the next stage of the conflict, Healey declined to say if he had faith in the US’s endgame – or if he trusted whether the administration had a coherent plan for the aftermath.

“It’s for the US to set out – our focus now, my focus as defence secretary – is making sure I do everything I can in a period where the Iranian threats and the Iranian strikes are increasingly indiscriminate [to] protect British people, military serving on bases like this to protect allies and protect this island, we protect our allies,” he said.

“We can respond to the requests we are getting from allies and step up and help their defence. We’ll do that in a coordinated way and we’ll do that as we’ve done from day one with Britain playing that leading role. We are doing what we need to do now to reduce the risk and do our best to protect British people, British bases, British allies.”

Healey said he did not accept the UK was underprepared for the initial strikes or the scale of the Iranian retaliation. On Thursday, the government announced it was sending four more Typhoon fighter jets and two attack helicopters to the region, although a Royal Navy destroyer remains in Portsmouth.

“We had already, weeks ahead of this conflict, already strengthened air defences here on the island of Cyprus. Not just to defend this base and our British forces personnel but the island of Cyprus and neighbouring allied countries,” said Healey.

“We put extra air defences and fast jets into Qatar as well to do the same thing. So we are leading a coordinated regional defensive operation that we expected would be needed and that we’ve flown and helped lead from day one of this conflict.”

The defence secretary suggested the UK was unlikely to step up operations further in the short-term, saying the country was “playing the role that we can best play.”