Indian Sterlite Industries, a subsidiary of London-listed Vedanta Resources, on Tuesday confirmed an improved offer for the operating assets of bankrupt U.S. copper miner Asarco LLC.

Sterlite, battling Mexican miner Grupo Mexico for control of Asarco, said its revised offer included cash of $1.587 billion, up from $1.1 billion, and a $208 million copper price participation note, down from $770 million.

The new bid reflected an increase in copper prices and the expectations of creditors, it said.

Sterlite and Grupo Mexico are facing off in a Texan court in the final stage of a year-long tussle for the copper miner, which sought court protection in 2005 amid a worker strike and more than $1 billion of environmental damage and asbestos claims.

Asarco lawyer Jack Kinzie said on Monday that Starlite's revised bid was worth $1.67 bln, including a note to creditors with a net present value of $83 million.

Grupo Mexico also upped its bid on Monday, increasing the cash portion by $260 million and bringing its value to $2 billion, a lawyer for Grupo Mexico told Reuters.

(Reporting by Paul Sandle; Editing by Dan Lalor)