US Republican Senator Lindsey Graham has died following a brief and sudden illness.

His office has released a statement saying he died on Saturday evening. “Senator Graham’s family appreciates prayers at this time and asks for privacy during this incredibly difficult period.”

Elected to the Senate in 2002, the South Carolina politician was one of Washington’s most influential voices on foreign policy and a key ally of Trump.

He had just returned from Kyiv, where he met the Ukrainian President Volodymyr Zelensky on Friday. There were no known health concerns ahead of his trip.

In a social media post marking the senator’s death, US President Donald Trump said Graham was a “true American Patriot”.

Graham also served as Chairman of the Senate Budget Committee.

He was a strong proponent of US support for Ukraine. “Putin will not stop in Ukraine,” he told the BBC in 2023.

“To be weak in Ukraine means that you lose in Taiwan,” he said.

In his most recent trip to Ukraine, Graham was working on a version of the Russia sanctions bill, which he said would give “tools to President Trump to end this war.”

Over the years, Graham clashed with President Trump, but he became one of his staunchest backers.

He told the BBC in 2023: “There is a dark side to Donald Trump… and he was a very good president. But I am sticking with him because I saw what he did,” citing Trump’s record on the US southern border, the killing of Iran’s Qasem Soleimani and the appointment of conservative judges.