New Delhi, Sept. 2 -- Venezuelan President Nicolas Maduro on Monday said he "would constitutionally declare a republic in arms" if the South American country were attacked by forces that the United States government has deployed to the Caribbean.

His comments during a news conference come as the U.S. government this week is set to boost its maritime force in the waters off Venezuela to combat threats from Latin American drug cartels. The U.S. has not signaled any planned land incursion by the thousands of personnel being deployed. Still, Maduro's government has responded by deploying troops along its coast and border with neighboring Colombia, as well as by urging Venezuelans to enlist in a civilian militia.

"In the face of this maximum...