Limbaugh, who pioneered the US media phenomenon of conservative talk radio and became an enthusiastic combatant in the US culture wars, had announced in February 2020 that he had been diagnosed with advanced lung cancer.

Limbaugh's appeal and the success of his top-rated radio show arose from his brash and colourful style, his delight in baiting Democrats and his promotion of conservative and Republican causes and politicians.

His radio show became syndicated across the US in 1988 and quickly built a large and committed following, making him wealthy in the process.

Former US president Donald Trump awarded Limbaugh the highest US civilian honour - the Presidential Medal of Freedom - during his 2020 State of the Union address to a joint session of Congress.

First lady Melania Trump placed the medal around his neck after her husband lauded Limbaugh as "a special man beloved by millions of Americans" and "the greatest fighter and winner that you will ever meet".

Illustrating Limbaugh's divisiveness, some Democratic lawmakers were heard groaning "oh no" while House of Representatives Speaker Nancy Pelosi - one of his favourite punching bags - sat in stony silence.

Trump honoured Limbaugh a day after the radio star announced his cancer diagnosis.

Limbaugh at the time said he planned to continue to do his program "as normally and as competently" as he could while he underwent treatment.

Limbaugh had experienced a variety of medical problems over the years including a loss of hearing reversed by a cochlear implant as well as an addiction to prescription painkillers that landed him in rehab in 2003.

Limbaugh - who called his followers "ditto heads" - espoused an unflinchingly populist brand of conservatism during a daily show broadcast on more than 600 radio stations across the US.

Australian Associated Press