O2 is threatening legal action against UK telco Liquid Telecom for using bubbles and the colour blue in its ads.

The giant mobile phone outfit claims that Liquid Telecom - whose ad features sea horses and pebbles, among other watery images - is infringing O2's "bubbles" and the colour "blue" trademarks which it uses in its own advertising and marketing.

O2 has asked Liquid Telecom "not to use bubbles or bubble imagery in any future advertising material" and asked for assurances that it will comply with its wishes.

Colin Loubser, MD of Liquid Telecom told The Register: "I'm astounded by this. We're seeking legal advice."

An O2 spokesman told us: "We're a big company and we deal with all sorts of instances of businesses trying to take us on. We will always defend our brand and any occasions when we feel our trademark is being infringed."

This isn't the first time O2 has become all protective about its bubbles. Last year it began legal proceedings against rival mobile operator 3 for using "bubbles" in its ad. That case is due to be heard later this year.

Elsewhere, mobile operator Orange is suing EasyGroup to stop it using the colour orange for its no frills easyMobile phone service. ®

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