A close associate of Belmoktar blamed the West for France's recent air and ground intervention against Islamist fighters in Mali.
"It's the United Nations that gave the green light to this intervention and all Western countries are now going to pay a price. We are now globalizing our conflict," Oumar Ould Hamaha told The Associated Press by telephone Wednesday night from an undisclosed location.
French President Francois Hollande launched the surprise operation in Mali, a former French colony in West Africa, on Friday, hoping to stop the al-Qaida-linked and other Islamist extremists whom he believes pose a danger to the world.
Further kidnappings could well be on the horizon, warned Sajjan Gohel, the international security director for the Asia-Pacific Foundation.
"The chances are that this may not be a one-off event, that there could be other attempts in Africa - especially north and western Africa - to directly target foreign interests," he said. "It's unclear as to what fate these individuals may meet, whether these terrorists are going to want a ransom or whether they'll utilize this for propaganda purposes."
Wednesday's attack in Algeria began with an ambush on a bus carrying employees from the massive gas plant to the nearby airport but the attackers were driven off, according to the Algerian government, which said three vehicles of heavily armed men were involved.
"After their failed attempt, the terrorist group headed to the complex's living quarters and took a number of workers with foreign nationalities hostage," the government said in a statement.
Attacks on oil-rich Algeria's hydrocarbon facilities are very rare, despite decades of fighting an Islamist insurgency, mostly in northern Algeria.
In the last several years, however, al-Qaida's influence in the poorly patrolled desert of southern Algeria and northern Mali and Niger has grown and the group operates smuggling and kidnapping networks throughout the area. Militant groups that seized control of a vast section of northern Mali last year already hold seven French hostages as well as four Algerian diplomats.
Prime Minister David Cameron's office said "several British nationals" were involved, while Japanese news agencies, citing unnamed government officials, said there are three Japanese hostages.
Late Wednesday, Statoil said five employees -four Norwegians and a Canadian - were safe at an Algerian military camp and two of them had suffered minor injuries. It said 12 employees were unaccounted for.
The Norwegian newspaper Bergens Tidende said a 55-year-old Norwegian working on the site called his wife to say he had been abducted.
Algeria had long warned against any military intervention against the rebels in northern Mali, fearing the violence could spill over its own long and porous border. Though its position softened slightly after Hollande visited Algiers in December, Algerian authorities remain skeptical about the operation and worried about its consequences on the region.
Algeria, Africa's biggest country, has been an ally of the U.S. and France in fighting terrorism for years. But its relationship with France has been fraught with lingering resentment over colonialism and the bloody war for independence that left Algeria a free country 50 years ago.
Algeria's strong security forces have struggled for years against Islamist extremists, and have in recent years managed to nearly snuff out violence by al-Qaida in the Islamic Maghreb around its home base in northern Algeria. In the meantime, AQIM moved its focus southward.
AQIM has made tens of millions of dollars off kidnapping in the region, abducting Algerian businessmen or politicians, and sometimes foreigners, for ransom.