An Iraqi official says authorities have shut the country's only border crossing with Jordan over security concerns, cutting a key route through a part of the country that has been the center of anti-government protests.

The prime minister's spokesman, Ali al-Moussawi, did not specify the nature of the security fears Wednesday, and said the closure was not intended to pressure protesters.

The highway from Baghdad to the Jordanian border runs through the vast Sunni-dominated province of Anbar. Protesters in the provincial capital Ramadi and other nearby areas have been protesting for more than two weeks along the highway over perceived second class treatment by the Shiite-dominated government.

The heavily traveled highway is Iraq's one of most vital routes for travelers and commerce.