LINDSEY Graham hauntingly joked: “I can’t die right now – I still need to sanction Russia,” after his final call with Donald Trump just hours before his death.

from a “brief and sudden illness” the day after he met Volodymyr Zelensky to hash out a fresh sanctions bill against the Kremlin.

U.S. Senator Lindsey Graham (R-SC) speaks to the media in KyivUS senator Lindsey Graham reached a Russian sanctions bill deal just before his death aged 71 Credit: Reuters : Former U.S. President Trump unveils his leadership team, in ColumbiaGraham was one of Donald Trump’s closest allies Credit: Reuters

is also understood to have discussed bolstering Ukraine’s air defences so that it could deal with the ballistic missile threat and visited a drone manufacturing depot.

A foreign policy hawk who fiercely defended Ukraine, Graham branded Vladimir Putin a “thug and a bully” and was one of the first to support sending the nation defensive weapons after Crimea was annexed in 2014.

His final public act was to reach a deal with a bipartisan panel of senators to impose sanctions on buyers of Russian oil.

After visiting Kyiv on Friday, Graham said: “I have never been more optimistic than I am today that we have the formula to end this war.

“Help Ukraine be more lethal. Let those supporting Russia to know there’s going to be a price to be paid if you keep doing it.

“And to try to find an off-ramp — not to humiliate Putin, but to end this war so that Ukraine will thrive and survive.

“I think we’ve got the best chance since I’ve been coming here in the last five years to get Putin to the peace table.”

, he doubled down on his sanctions bid and discussed possible strikes on Iran.

US Senator Graham meet with Ukrainian President Zelensky in KyivGraham visited Ukraine and Volodymyr Zelensky last week in his 10th visit Credit: EPA Graham TrumpTrump called Graham ‘one of the greatest people I have ever known’ Credit: AP

He complained of feeling ill after the call, but pressed on with a scheduled broadcast and even quipped: “I can’t die right now. I still need to push through sanctions against Russia!”

The US president paid tribute to the late lawmaker and revealed that Graham “sounded a little tired” on the phone in the hours before his death.

Graham died of “aortic dissection due to arteriosclerotic cardiovascular disease,” according to the Medical Examiner of the District of Columbia’s preliminary findings.

That is effectively when the aorta is damaged or develops a leak, according to a statement released by his office on Sunday.

The statement added that an official death certificate will be pending until all the toxicological and microscopic testing are finalized.

At that point, the death certificate will be updated to reflect the cause of death and appropriately classify the manner of death.

First responders rushed to the senator’s Washington home after receiving reports of a person suffering from cardiac arrest, according to dispatch audio obtained by CNN .

Tributes have since flooded in for the South Carolina native, who was one of America’s strongest proponents of national defence and a key ally to Kyiv.

Zelensky called him “a true champion of freedom and the values that make our world safer”.

In a statement on X, he added: “He visited Ukraine ten times during the years of Russia’s full-scale invasion and was here with our people when it was most needed.

“We remained in constant dialogue, and I will miss our conversations. We met twice in just the past week.

“A staunch advocate for bipartisan and bicameral support for Ukraine, in recent weeks, he had been working on important initiatives that could help bring peace closer, including stronger sanctions against Russia.

“We will always be especially grateful for the recognition of our people and words of admiration for the courage of Ukraine’s defenders.

“America and the world have lost a determined leader. Our condolences go out to Lindsey’s family, loved ones, and everyone who had the privilege of working alongside him.”

FBI Director Kash Patel paid tribute to Graham, saying: “Senator Lindsey Graham was a devoted public servant, a fierce defender of our nation, and a true patriot who dedicated his life to the people of South Carolina and the United States.

“Our prayers are with his family, loved ones, colleagues, and all those who knew him during this devastating time.

“The FBI is assisting local authorities and has made every necessary resource available.”

Graham had been targeted by plots from Iranian leaders, with state media sickly celebrating his death on Sunday.

One regime broadcaster congratulated “the Iranian people on the death of U.S. Senator Lindsey Graham, who has been sent to hell.”

Graham was a former Trump critic who became one of the president’s closest allies.

Reacting to Graham’s death, Trump said on Sunday: “What makes it even stranger is that I got a call last night sometime in the early evening maybe in the sevens.”

The president said the senator had just landed from Ukraine and was “pushing the Save America Act like crazy”.

He remembered his ally “sounded a little tired, but perfect,” adding: “He had a right to be (tired). He was a worker.”

“And then that was it.

In a post on Truth Social earlier, the president wrote: “Senator Lindsey Graham, one of the greatest people and Senators I have ever known, is dead!”

The president ordered that flags across the country be flown at half-mast until Saturday evening.