US Republican presidential candidate Marco Rubio compares outrage over 'dead babies' to Cecil the lion

Mr Rubio asked on Twitter where the outrage was over 'the planned parenthood dead babies'

Marco Rubio has attracted some attention by wading into the Cecil the lion controversy (AP)

A Republican presidential candidate has compared the outrage over the shooting of a famed African lion to the lack of anger after a controversial abortion video was aired in the US.

Florida senator Marco Rubio tweeted on Wednesday asking his 700,000 followers where the outrage was over "the planned parenthood dead babies" in comparison to the international furore erupting around the death of a famous African lion killed by a US hunter earlier this month.

A video released earlier this month purports to show individuals from Planned Parenthood, a non-profit group that provides reproductive and maternal healthcare, discussing the sale of aborted foetal material.

The video has made waves in the US and has been roundly denounced by the group as part of a year-long pattern of illegal harassment by anti-abortion pressure groups.

Mr Rubio is the latest Republican candidate – alongside Rand Paul from Texas and Ted Cruz from Texas – to condemn the video. Democratic frontrunner Hillary Clinton has also called the video “disturbing,” but defended the nationwide organisation.

Meanwhile, the controversy around Walter Palmer – the Minnesota dentist who shot Cecil the lion in Zimbabwe – has only increased.

Mr Palmer, who has always maintained he understood the £35,000 ($55,000) shoot to be legal, has apologised to his patients as calls for him to be prosecuted mounted.

Around 100 protesters gathered outside Mr Palmer’s surgery yesterday. Mr Palmer was nowhere to be seen.