Portugal decided against upgrading its US-made F-16 fighter jets to the more advanced F-35s due to Donald Trump, marking one of the first instances where the US president’s actions derailed a major arms deal.

The Portuguese Air Force had advised purchasing Lockheed Martin F-35s, but when outgoing Defense Minister Nuno Melo was asked by Portuguese media Público if the government would act on that recommendation, he responded: "We cannot ignore the geopolitical environment in our choices. The recent position of the United States, in the context of NATO ... must make us think about the best options, because the predictability of our allies is a greater asset to take into account."

Amid the dramatic realignment under Trump — who reiterated his intention to annex Greenland and threatened Canada — concerns have arisen that the US government might block access to software updates and spare parts required to make the F-35 fully operational.

"The world has changed ... and this ally of ours ... could bring limitations to use, maintenance, components, and everything that has to do with ensuring that aircraft will be operational and used in all types of scenarios," Melo said.

He added, "There are several options that must be considered, particularly in the context of European production."

A spokesperson for the jet maker said, "Lockheed Martin values our strong partnership and history with the Portuguese Air Force and looks forward to continuing that partnership into the future. The F-35 is the most advanced, survivable, and connected fighter aircraft in the world, enabling 21st Century Security and allied deterrence. Questions about foreign military sales of the F-35 are best addressed by the US government."

Dutch Defense Minister Ruben Brekelmans stated earlier this week that the Netherlands would not cancel its contract for the jets. However, Portugal has yet to sign a deal, and the country is currently facing a snap election following the collapse of its center-right government.

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This comes amid geopolitical tensions sparked by Trump's ongoing statements about annexing and taking over nations. Trump urged NATO Secretary General Mark Rutte to support Washington in “securing” Greenland, discussing the matter during their meeting in the Oval Office on Thursday.

Trump first proposed purchasing the Danish autonomous territory in 2019 and has revived the idea since returning to office. Speaking at a recent joint session of Congress, he declared that the US would secure the island “one way or the other.”

When asked by journalists on Thursday about the “potential annexation of Greenland,” Trump responded, “I think it will happen.” Turning to the NATO chief, he added, “I didn’t give it much thought before, but I’m sitting with a man who could be very instrumental. You know, Mark, we need that for international security. We have a lot of our favorite players cruising around the coasts, and we have to be careful. We’ll be talking to you.”

Rutte, however, downplayed the idea, chuckling as he replied, “When it comes to Greenland, joining or not joining the US, I would leave that outside... this discussion, because I do not want to drag NATO into that.”

Trump reiterated Greenland’s strategic importance, emphasizing, “I think that’s why NATO might have to get involved in a way.” He also pointed out the existing US military presence on the island, stating, “We have a couple of bases and quite a few soldiers in Greenland. Maybe you’ll see more and more soldiers go there.”