By Tom Bergin

LONDON (Reuters) - BP Plc has filed a lawsuit against Halliburton, the company that cemented the blown-out well which caused the Gulf of Mexico oil spill, a day after claiming $40 billion from rig owner Transocean.

BP said Halliburton concealed critical information which could have prevented the disaster.

BP did not give a figure for how much money it was seeking from Halliburton but asked for damages of up to the total cost of the spill, which BP has put at $42 billion, plus interest, legal costs and punitive damages.

"Halliburton's improper conduct, errors and omissions, including fraud and concealment, caused and/or contributed to the Deepwater Horizon incident," BP said in a court filing.

"Halliburton knew and understood it was misrepresenting material information," BP added.

The suit was filed on Wednesday, one year to the day after the Deepwater Horizon rig exploded, killing 11 men. On Wednesday, BP also filed a lawsuit against rig operator Transocean.

Since the outset of the disaster, BP has sought to blame its contractors, namely Transocean. The Presidential investigation into the report did criticize these companies but levied most of its criticism against BP.

BP shares traded up 0.9 percent against a 0.4 percent rise in the STOXX Europe 600 Oil and Gas index at 3:10 a.m. EDT.

Analysts have said they expect some form of settlement between the companies involved and that the contractors will end up making some contribution to the final bill.

In January Halliburton disputed a U.S. presidential commission's characterization of its cementing work on the blown-out Macondo well, saying that its report omitted key facts.

(Additional reporting by Sakthi Prasad in Bangalore; Editing by Mike Nesbit)