Evan Vucci, Associated Press
Republican presidential candidate, former House Speaker Newt Gingrich speaks during a campaign stop at Food City on Monday, March 5, 2012 in Knoxville, Tenn.

CHATTANOOGA, Tenn. — Republican presidential candidate Newt Gingrich is calling for eliminating the government of Iran if it blocks passage through a key oil route in the Mideast.

Campaigning in Tennessee ahead of Tuesday's GOP primary, the former House speaker said the U.S. should declare war if Iran attempts to close the Straits of Hormuz, through which 20 percent of the world's oil exports pass.

Gingrich says that the U.S. should send the message that any threat to close the Straits of Hormuz would be considered an act of war and that the U.S. will eliminate the government of Iran.

President Barack Obama said Monday that the United States would strike Iran in order to prevent the nation from acquiring nuclear weapons but condemned what he labeled "loose talk of war."