Tensions rise over Iran's nuclear program

TEHRAN, Iran -- Iran began ground military exercises Saturday and defiantly warned that it could cut off oil exports to "hostile" European nations as tensions rise over suggestions that military strikes are an increasing possibility if sanctions fail to rein in the Islamic Republic's nuclear program.

Iran's Supreme Leader Ayatollah Ali Khamenei issued warnings against any possible American or Israeli attacks against Tehran's nuclear facilities. Western forces have boosted their naval presence in the Gulf led by the American aircraft carrier USS Abraham Lincoln.

Washington and its allies fear Iran could use its uranium enrichment labs -- which make nuclear fuel -- to eventually produce weapons-grade material. Tehran insists it only seeks reactors for energy and medical research.

-- AP