While meeting with US troops in Poland over a pizza lunch, president Joe Biden shared an anecdote about visiting his late son Beau, who served in the Iraq War.

Years ago, the president said, he tried to visit Beau in Baghdad, but had trouble finding him.

“I walked in and I was looking for my son, and I’m going around wondering, ‘Where the hell is my son?’” Mr Biden told the soldiers. When he finally found him, he realised his son had used a different surname on his name-tag.

“I said, ‘What happened?’” the president recalled. “And he said, ‘Dad, with the name Biden everybody thinks something’s going on.”

Mr Biden then offered to provide the same service for others.

“So if any of you have to change your names, let me know, OK?” the president said.

Mr Biden met with service members of the 82nd Airborne Division in Rzeszow, Poland on Friday, not far from the Ukrainian border. Mr Biden has sent thousands of additional troops to Eastern Europe to bolster Nato’s defenses as the war in Ukraine continues.

The Russian invasion of Ukraine is now in its second month. The United Nations estimates that at least 1,035 Ukrainian civilians have died in the war so far, and 1,650 have been injured. Meanwhile, more than 3.7 million people have fled the country.

Many of those refugees have come to Poland, and the troops Mr Biden spoke to have been helping them find food and shelter. On Friday, the president personally thanked them.

“Thank you very, very much for all you do,” Mr Biden said. “You are the finest fighting force in the history of the world, and that’s not hyperbole.”