SANTIAGO, April 29 (Reuters) - Copper output from

Chile's state-run Codelco rose 22% in April compared to the same

period a year before, Chairman Maximo Pacheco said on Tuesday.

He added that he is optimistic on securing the approval of

China regulators for a joint venture with lithium producer SQM,

and that the Codelco board will select a partner for the

Maricunga lithium project within the coming weeks or months,

after receiving binding offers from global companies in March.