IZVORANI, Romania (Reuters) -Romania's far-right presidential frontrunner said on Wednesday he will oppose continued Ukrainian grain exports through Romania and further military aid to Kyiv if elected, and that Bucharest is not obliged to stick to NATO's defence spending commitments.

Speaking to Reuters in an interview ahead of a presidential run-off vote on Sunday, Calin Georgescu also questioned the effectiveness of European Union funding and said Romania would come first should he win.

If Georgescu defeats pro-European centrist Elena Lasconi in the run-off, Romania could become isolated on the West's eastern flank and its key support for Ukraine against Russia's 2022 invasion could collapse.

Since Russia attacked Ukraine, Romania has helped export millions of tons of Ukrainian grain through its Black Sea port of Constanta, trained Ukrainian fighter pilots and donated a Patriot air defence battery to Kyiv.

All of that will stop should he win, Georgescu said.

"How could I agree to that? It is impossible. Romania and the Romanian people come first.

"It is unimaginable that there be a war next to us in the middle of Europe, so a priority will definitely be that this war in Ukraine must immediately be stopped."

Asked if he supported NATO's commitment to spend 2% on defence annually, a stance held by U.S. President-elect Donald Trump, whom Georgescu admires, he said: "This is ultra-secondary, I am not even interested."

"The concern of the Romanian people is to be happy. (They) cannot be happy spending money on other things. If NATO is defensive, than it should remain defensive. I believe one thing. Romania has an obligation to no one."

(Reporting by Luiza Ilie; editing by Alan Charlish and Mark Heinrich)

By Luiza Ilie