Hillary Clinton has picked her running-mate in the US presidential election coming later in the year

Hillary Clinton and Tim Kaine

Democratic presidential candidate Hillary Clinton has picked Virginia Senator Tim Kaine as her running mate.

The former Secretary of State confirmed her choice on Twitter, saying: "I'm thrilled to announce my running mate, @timkaine, a man who's devoted his life to fighting for others - H."

Mr Kaine responded: "Just got off the phone with Hillary. I'm honored to be her running mate. Can't wait to hit the trail tomorrow in Miami!"

The pair will appear together on Saturday at Florida International University.

Mr Kaine could give Mrs Clinton a boost in his home state of Virginia, a pivotal battleground in November's White House election.

The welder's son could also help her woo white male voters, a demographic she has consistently struggled to win over.

But liberals are wary of his support for fast-track approval of the Trans-Pacific Partnership, a free trade deal that has come under fierce attack from both the political left and the right.

Mr Kaine, 58, is a Spanish-speaking, Harvard-trained lawyer, who cut his political teeth as mayor of Richmond, Virginia.

He became the state's governor, before his election to the Senate, where he has been active on foreign relations and military affairs.

Other possible Democratic VP finalists were said to include Agriculture Secretary Tom Vilsack, Labor Secretary Tom Perez, Massachusetts Senator Elizabeth Warren, New Jersey Senator Cory Booker and Ohio Senator Sherrod Brown.

Mrs Clinton will be anointed as the party's official presidential candidate along with Mr Kaine at next week's Democratic National Convention in Philadelphia.

Her VP announcement was timed to snatch the limelight from newly minted Republican nominee Donald Trump, hours after he closed his convention with a fiery speech.