Rep. Todd Akin continued his major-networks apology tour on Wednesday, facing a firestorm for his comment that 'legitimate rape' does not usually lead to pregnancy.

To date, GOP presidential candidate Mitt Romney has refused to be drawn on the controversy but both he and his running mate Paul Ryan have publicly called for the Missouri politician to step aside.

During an interview on NBC’s Today this week, Akin confirmed that Ryan personally telephoned him to urge him to withdraw from the race.

'He advised me that it would be good for me to step down,' Akin told NBC. 'I told him that I was going to be looking at this very seriously, trying to weigh all of the different points on this and that I would make the decision.'

But according to the Daily News, to date Akin has remained defiant in the face of all calls for him to drop out of the Missouri U.S. Senate race.

Behind the scenes Republicans have reportedly been pressuring Akin to voluntarily withdraw from the race and allow the GOP to replace him with a less controversial candidate against Democratic Senator Claire McCaskill.

Akin is refusing to go quietly however. Speaking on Sean Hannity’s radio program on Tuesday, he sniped at Mitt Romney directly saying, 'Why couldn’t he run his race and I’ll run mine?'

It is not right for the Republican elite in Washington to overrule the wishes of the Missouri Republicans who voted for him in the Senate primary, Akin added.

Meanwhile he reiterated that his controversial comments about rape at the weekend were an isolated mistake.

'The word 'legitimate' never has a good reason to be standing next to the word 'rape' he told NBC.

He also admitted that he had offered medical evidence that was entirely wrong.

'I was medically wrong. Yes, pregnancy can happen as a result of rape,' he said.

Meanwhile, Akin has confirmed that he will skip the GOP convention in Tampa next week, at the request of top Republicans.