Reykjavik, Iceland - President Donald Trump's nominee for ambassador to Iceland has apologized after suggesting the island country could become the US' 52nd state.

According to Politico, former Republican Representative Billy Long said on the House floor Tuesday that Iceland will be the 52nd state, with himself as governor.

Long is Trump's pick to serve as US ambassador to Iceland.

The ex-congressman's comments – which he has dismissed as a joke – came amid Trump's growing push to annex Greenland, despite overwhelming opposition from the local population. They also follow the US' recent invasion of Venezuela and abduction of President Nicolas Maduro.

The Icelandic Foreign Ministry said it had reached out to the US embassy in Reykjavik for clarification of the remarks.

Meanwhile, a petition urging Iceland's Foreign Minister Þorgerður Katrín Gunnarsdóttir to reject Long as ambassador has garnered thousands of signatures.

Long has since tried to walk back his comments.

"There was nothing serious about that, I was with some people, who I hadn’t met for three years, and they were kidding about [Louisiana Governor] Jeff Landry being governor of Greenland and they started joking about me and if anyone took offense to it, then I apologize," he told Arctic Today.

"I apologize and that’s my only comment, I look forward to working with the people of Iceland and I apologize it was taken that way, I was with a group of friends and there was nothing serious about it," he added.