LONDON -- Vodafone (VOD) (VOD 0.87%) is believed to have increased its offer for Kabel Deutschland following a rival bid from Liberty Global (LBTYA 2.10%).

This time last week, Vodafone confirmed it had made a preliminary approach regarding a possible offer for the company, though Bloomberg had claimed that formal talks between the companies were yet to start because the indicated bid of 80 euros to 82 euros per share was "too low."

However, days after the announcement, U.S. company Liberty Global made a firm offer of 85 euros per share, valuing Kabel Deutschland at 7.5 billion euros, or 6.4 billion pounds.

Bloomberg has now reported that Vodafone has matched Liberty's bid, as the boardrooms take up positions at either end of a tug-of-war with Germany's largest cable operator in the middle.

The plot takes another twist, when you consider that as recently as the beginning of last month, analysts at Citigroup declared that an acquisition of Liberty Global would be within Vodafone's reach, should it sell its 45% stake in Verizon Wireless.

Liberty is also currently negotiating a purchase of Virgin Media, which would instantly offer it a television service in the U.K. should it acquire the U.S. cable and telecoms company...

With neither firms currently commenting on the matter, there is little hard evidence to go on. But following Vodafone's ex-dividend date coming and going last week, combined with continued acquisition talk, the share price has been pushed down to 183 pence from a high of 200 pence less than a month ago. 

With many City analysts still recommending Vodafone as a buy -- particularly with the situation over Verizon Wireless yet to be resolved -- then today's price could offer an attractive buying opportunity for those interested in a high-yield stock with potential to grow... Personally, I see more upside in the shares and will continue to hold until I hear further, firm news on the deal.

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