Republican Senator Ted Cruz from the US state of Texas is about to announce his plans to run for the American presidency, according to an aide, reported Reuters.

Cruz would be the first major figure to announce his candidacy for the 2016 election.

The 44-year-old has built a reputation as a stubborn advocate for conservative principals and is currently favoured by 8 percent of Republicans.

Former Florida Governor Jeb Bush, brother of George W. Bush, leads the polls at 21 percent.