The Council of the European Union in June said it welcomed Yemeni efforts to find peaceful solutions to ongoing national security challenges but expressed concern about its stability since President Ali Abdullah Saleh resigned in 2012.
The EU said it was "specifically considered" about ongoing pressure on Yemen's territorial integrity from southern secessionists.
A Dutch couple kidnapped in June in Yemen appeared in an Internet video uploaded last weekend saying they need urgent help or they'll be killed by their terrorist captors in less than two weeks.
The U.S. State Department issued a travel warning advising against all travel to Yemen because of terrorist activities and civil unrest.
"U.S. citizens currently in Yemen should depart," the Tuesday warning said. "The security threat level in Yemen is extremely high."
Al-Qaida in the Arabian Peninsula called for more homegrown attacks on the United States in a 6-minute video posted online in early June. The al-Qaida franchise, which counts Yemen as its base of operations, has been linked to terrorist plots on the United States and Europe.
U.S. Army Maj. Nidal Hasan faces charges in a military court for the killing 13 people at the Fort Hood military base in 2009. Inspired by AQAP, he said his actions were justified by U.S. military intervention in Afghanistan.