British oil giant BP is calling for reliable security at its sites in Algeria, following a deadly January attack by Islamists, or it could postpone investment in the country, the APS news agency said on Thursday. BP has asked its Algerian partner, Sonatrach, \"for reliable security conditions to continue its investments as planned,\" APS said, quoting an unnamed source. \"They have effectively said that if security conditions do not fundamentally improve, they could postpone certain investments,\" the source was quoted as saying. In January, Islamist gunmen took hundreds of hostages when they overran a site jointly run by BP, Norway\'s Statoil and Sonatrach near In Amenas in the southern Algerian Sahara desert. A four-day siege and two rescue attempts by the Algerian army resulted in the deaths of 38 hostages -- 37 foreigners and an Algerian. The Algerian government has refused to let BP provide its own security through private companies. \"We are open to any idea as long as it does not touch on our sovereignty,\" the source said. \"But at the same time, we are conscious of the fact that security conditions must be improved to save human lives.\" Meanwhile, the source said that, contrary to press reports, BP had not told Sonatrach it was delaying gas projects in In Amenas and In Salah, also in the south, that had been planned for next year.