Vodafone is expected to come under heat to disclose if it bid on AT&T Wireless last week. Cingular is said to have put in an all cash offer between $31.9 and $35 billion .

If Vodafone did put in an offer, it was rumored to go as high as $35 billion. AT&T Wireless will make a decision by the end of the month.

Update: According to the Wall Street Journal, Vodafone made an offer around $35 billion. We have a bidding war folks.