The US Rapper Kanye West on Sunday, in Charleston, South Carolina, has officially launched his campaign for the 2020 US presidential election with rambling rally to expel Donald Trump as president in November elections.

With tears on the eyes, West gave a speech in which he claimed he had wanted his wife, Kim Kardashian, to get an abortion and that renowned American abolitionist Harriet Tubman "never actually freed the slaves."

"My dad wanted to abort me. My mom saved my life. There would've been no Kanye West because my dad was too busy," he added.

He later speak loud, "I almost killed my daughter! I almost killed my daughter!"

At the event, the rapper seemed to make policy decisions off-the-cuff and made several rants, including on abortion and on abolitionist Harriet Tubman.

However he then added that he believes abortion should remain legal, but there should be financial support for struggling new mothers - suggesting that "everybody that has a baby gets a million dollars".

West who has left voters befuddled over whether his campaign is genuine or a publicity stunt to help sell albums or merchandise, delivered rambling remarks during the event at a Charleston, South Carolina, wedding venue and convention center.