Trump calls Clinton pick 'Corrupt Kaine'

Republican presidential nominee Donald Trump's campaign already has a nickname for Hillary Clinton's new running mate: "Corrupt Kaine".

The Trump campaign calls Virginia senator Tim Kaine "ethically challenged", citing a Politico report that he accepted $US160,000 in gifts from 2001 to 2009, when he was Virginia's lieutenant-governor and governor.

Trump's senior communications adviser Jason Miller said: "The status quo ticket of Clinton-Kaine wants us to believe in a rigged system that enriches them at your expense."

Earlier on Friday, Trump sent supporters a text calling Clinton, Kaine and President Barack Obama "the ultimate insiders".

Clinton announced on Friday night that Kaine would join her ticket. The running mates will campaign together in Miami on Saturday.