It would give Carnival - currently banned under UK Takeover Panel rules from upping its bid again until after the 14 February meeting - an opportunity to put together a more tempting offer.

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In a statement, Nestle said its decision not to make, or participate in, a formal offer for Cadbury followed discussions with the UK Takeover Panel - the body in charge of regulating takeovers.

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But after all the weeks of febrile speculation about Vodafone, it is reasonable to assume that the UK's Takeover Panel and the Financial Conduct Authority would want investors to know what is going on, and would therefore put pressure on putative bidders to show their hand.

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Tesco is expected to be asked by the Takeover Panel, responsible for mergers and acquisitions in the UK, to make a "put up or shut up" statement about its intentions.

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