"The Algerian authorities have received assurances that firms and foreign employees will not leave Algeria, " said Energy Minister Youcef Yousfi.

BBC: In Amenas siege: Is Algeria's economy under threat?

As Western leaders condemned the kidnappings, Algerian Energy Minister Youcef Yousfi said Algeria would boost security at its energy installations without outside help.

BBC: Algeria crisis: Hostage-takers 'taken alive' at gas plant

The plant, which is responsible for more than a tenth of Algeria's overall gas output, is expected to resume production by Tuesday, Algeria's Energy Minister Youcef Yousfi said.

BBC: Algeria crisis: Hostage death toll 'rises to 48'