SANAA, Feb. 21 (Xinhua) -- Yemen has closed off main waterways leading to its seacoasts at the Gulf of Aden and Red Sea in a bid to prevent "African infiltrators" from entering its soil, the Interior Ministry said Sunday.

The ministry has already commanded the Police Coast Guard (PCG) at the coastal provinces on the Gulf of Aden and Red Sea to shut out the main waterways to ward off African illegal immigrants from infiltrating into the Yemeni territories, read a statement issued by the ministry on its website.

It said this step came in line with the efforts exerted by the Yemeni government to bar "terrorist elements in the Horn of Africa" from sneaking to the Yemeni soil, specially after Somali- based wing of al-Qaida Young Mujahideen (al-Shabab al-Mujahideen) announced its intention to support the Yemeni-based branch of al- Qaida in the Arabian Peninsula.

"The security agencies have been keeping the Somali refugees in Yemen under constant surveillance," said the ministry, confirming - at the same time that the Yemeni government's commitment to meet obligations towards supporting Somali refugees has not changed.

"The government is keen to continually providing appropriate living conditions for their (Somali refugees) stay on its territory," the ministry added.

Sanaa government, which is stepping up efforts to solve a discontent among southern separate group and implement economic reforms after it ends a six-year fighting with northern Shiite rebels, came under mounting pressure from Washington to turn its focus on fighting al-Qaida affiliate activating within its borders.

Though Yemeni government has long welcomed Somali refugees fleeing their war-torn country and sailing to Yemen, the government is now particularly concerned that al-Qaida infiltrators could be among those new arrivals, local media said.

Yemen hosts 78,000 Somali refugees by the end of 2009 out of 171,000 total registered refugees, according to statistics of the UN refugee agency. Interior Ministry officials say many more Somalis are still unregistered.