WASHINGTON (REUTERS) - US Senator Rand Paul blamed Republicans and Democrats for heavy government spending in an address responding to President Barack Obama's State of the Union speech on behalf of the small-government, fiscally conservative Tea Party movement.

"Both parties have been guilty of spending too much, of protecting their sacred cows, of backroom deals in which everyone up here wins, but every taxpayer loses," Mr Paul said on Tuesday.

Mr Paul, the son of former Republican Texas Representative Ron Paul, a libertarian and three-time presidential candidate, won his Kentucky Senate seat with strong support from the Tea Party.

Despite being a relatively junior senator, Mr Paul, 50, has established himself as a strongly conservative voice on Capitol Hill, notably by telling then-Secretary of State Hillary Clinton last month that he would have fired her over the September attacks on the US diplomatic mission in Benghazi, Libya.

Mr Paul's remarks under the Tea Party banner prompted talk of division within the Republican Party.

But Paul's speech echoed many themes in the official Republican response to Obama's remarks by Senator Marco Rubio of Florida, who like Mr Paul was elected in 2010 with strong Tea Party support.

Mr Rubio is one of the leaders of a bipartisan push for immigration reform in Congress, and Mr Paul also said Republicans should push to overhaul immigration laws.

"We must be the party who sees immigrants as assets, not liabilities. We must be the party that says, 'If you want to work, if you want to become an American, we welcome you,'" said Mr Paul, whose father was a Republican presidential candidate last year.

Mr Paul had harsh words for Mr Obama, calling for a balanced budget and accusing him of seeking to "squeeze" working people to fund higher spending and big government.

"Big government makes it more expensive to put food on the table. Big government is not your friend. The president offers you free stuff but his policies keep you poor," Mr Paul said.