New Zealand mega-dairy Fonterra could well up its bid for Australian counterpart National Foods to see off competition from Filipino brewer San Miguel, analysts are speculating.

Independent Australian broker Austock is quoted by AAP as saying that Fonterra could well hike its bid by 15% to A$6.27 (US$4.77) per share, from its October offer of $5.45 per share.

However, dairy farmers are said to be wary about the prospect of Fonterra raising its bid

San Miguel offered $6 per share at the end of December in a bid backed by the board of National Foods.