State Department advises Americans not to travel within 50 miles of border with Yemen as 'groups plotting attacks.

Axar.az reports citing Middleeasteye that the US State Department has called on American citizens to "exercise increased caution" while traveling to Saudi Arabia, a travel advisory posted on its website said on Wednesday.

The department warned US citizens not to travel within 50 miles of the border with Yemen as "groups continue plotting possible attacks in Saudi Arabia".

"Terrorists may attack with little or no warning, targeting tourist locations, transportation hubs, markets/shopping malls, and local government facilities," it added.

"Iran has reiterated that it was not behind attacks on Saudi Arabia's oil facilities and it has warned that any move by America against Iran will get an immediate reaction."