22 March 2015
Last updated at 14:28
Senator Ted Cruz is to set out on Monday his plans to run for the US presidency in 2016, according to advisers.
The 44-year-old Texan is expected to announce his bid to seek the Republican nomination in a speech at Liberty University in Virginia.
He would be the first Republican candidate to declare his campaign.
Commentators say that Mr Cruz, a Tea Party favourite, splits opinion among his colleagues.
Mr Cruz may go up against the likes of Jeb Bush, an early Republican frontrunner, and New Jersey Governor Chris Christie, although they are yet to formally declare their candidacy.
Republican Senators Rand Paul and Marco Rubio have also hinted at their own White House interests.
Meanwhile Hilary Clinton is widely expected to be among those standing for the Democratic Party nomination.
Mr Cruz is a leading conservative who was elected to the US Senate in 2012.
In September 2013 the firebrand politician gave a 21-hour speech against Obama’s health law – one of the longest speeches in Senate history.
His eligibility to run for the White House was thrown into doubt after it emerged he was born in Canada, and he was forced to formally give up his dual citizenship last year.
2016 runners and riders
Clockwise from top left: Jeb Bush, Chris Christie, Ted Cruz, Elizabeth Warren, Rand Paul, Hillary Clinton
Most have not formally declared but these are some of the names to watch:
- early Republican frontrunner is Jeb Bush
- but New Jersey Governor Chris Christie could battle Bush for the party’s centre ground
- darling of the Tea Party is Texas Senator Ted Cruz
- firebrand liberal Elizabeth Warren is championed by many in the Democratic Party
- libertarian Rand Paul has his supporters – and enemies – among Republicans
- Hillary Clinton will have learnt much from her failed campaign of 2008