By Clara Denina, Pratima Desai and Felix Njini

LONDON (Reuters) - Commodities group Glencore is studying an approach for Anglo American, two sources said, a development that could spark a bidding war for the 107-year old mining company.

Glencore has not yet approached Anglo, one of the sources said. The discussions are internal and preliminary at this stage and may not result in an approach, the source added.

"We do not comment on market rumour or speculation," a Glencore spokesperson said.

Anglo on Friday rejected a $39 billion all-stock proposal from the world's No. 1 miner BHP Group.