Cadbury and U.S. rival Hershey have held talks over a possible friendly bid by the American firm, according to reports.

Sources claim Hershey was still considering a bid but did not want to enter a hostile auction battle with Kraft Foods, which made a formal £10.1 billion cash-and-share offer to Cadbury shareholders earlier this month.

The Birmingham-based confectioner, whose shareholders have until February 2 to decide whether to accept Kraft’s bid, has said it is not interested in a bid at that level and that its performance on revenue and margins means that a far higher offer is warranted.

Hershey and the charitable trust that controls the chocolate maker is still considering whether it will make a bid that is likely to include a higher cash element than Kraft’s, said the report, which added that any bid was unlikely to materialize before the New Year.

Cadbury is due to release a defense document, which is likely to reveal plans for growth beyond 2011 on both revenues and margins, on Monday.