A Republican senator has accused Donald Trump Jr of corruption and demanded a Senate investigation into revelations that a Russian oligarch bankrolled part of his recent wedding in the Bahamas.

John Curtis, of Utah, wrote to the leaders of the US Senate judiciary committee on Tuesday, urging them to subpoena Trump Jr over his business dealings, his relationships with foreign individuals, gifts he has received – and any occasions where his connection to his father, Donald Trump, “was invoked or understood to provide value”.

Trump Jr’s wedding warrants the kind of scrutiny Republicans once trained on Hunter Biden, the son of Joe Biden, Curtis said.

“A toaster is a wedding gift. A private-island party paid for by a Putin-connected oligarch is something else,” he wrote in a social media post accompanying the letter to the committee. “Republicans nearly wore out the subpoena machine investigating Hunter Biden’s foreign relationships. We should not unplug it now.”