The row between Google and a tiny British research firm contesting the use of the GMail trademark escalated tonight after the internet search giant was accused of making "inaccurate and misleading statements".

The normally taciturn Google hit back, telling Times Online that it felt that the British company in the dispute was principally interested in money.

Times Online today had sight of an e-mail exchange between Google and the chief executive of Independent International Investment Research (IIIR) - which is threatening legal action over the trademark for GMail.

In the e-mails, the IIR takes Google to task over official comments it made in response to his case.

Shane Smith wrote to Tu Tsao, Google's trademark lawyer in America, warning that he would try to refer the matter to the US Securities and Exchange Commission, which regulates public companies in the United States.

The exchange follows an official statement circulated to the media by Google in which it appeared to suggest there had been minimal contact between the two companies and that IIIR had provided no evidence to back up its claim.

IIIR had claimed that, through its Pronet subsidiary, it had launched its own branded G-Mail service - which gives subscribers use of web-based e-mails - nearly two years before Google launched its own Gmail offering. IIIR said last week that, after about 15 months of "correspondence and negotiations", it was considering legal action against Google.

After IIR made a further statement refering to the recent success of a similar claim in Germany, Google published an official comment about the case.

It said: "We can confirm that Pronet has contacted Google and that we have been seeking information on their use of the Gmail trademark but have not received any evidence to establish the rights they have claimed."

In response, Mr Smith wrote to Ms Tsao: "This emphatic statement means that a one-off event of contacting Google has occurred, and that my firm has made totally unsubstantiated claims.

"As you must be aware this is grossly misleading. It misrepresents the degree of telephone, fax, e-mail and letter contact that has in fact taken place over the last 16 months, between our companies directly, between our US attorneys and Google, and between our UK lawyers, myself and Google in conference."

As he revealed that the "wider recognition" for Google's version of Gmail had led some of IIIR's prospective clients to suspect his company of infringing intellectual property rights, Mr Smith added: "It is entirely unacceptable that our integrity should be tainted in this way. You have then aggravated this uncomfortable situation by effectively accusing my firm of lying, since your public statement is at odds with our own, entirely accurate, statement."

Ms Tsao replied, suggesting that IIIR had claimed to have the registered rights to Gmail and that Google's contested statement followed a press report. In fact, neither company has the registration to Gmail, although both have applied.

Ms Tsao wrote: "We made this statement in response to an article that indicated that you have a registration for GMAIL dating back to 2002. We have searched the various trademark databases, and have found no such registration. If you actually have such a registration, then we urge you to send us proof.

"Also, we are still waiting for evidence from you as to your common law rights in 60 countries and as to your actual customer base, which, at this point, is still unsubstantiated."

Mr Smith wrote back, saying: "Contrary to your statement, you asked us to provide evidence of prior use and we complied by providing material including screenshots from our real time application; copies of contracts; copies of promotional materials; photographs from trade shows; exhibition display material; extracts from annual reports; screen shots from the website.

"The fact that there is a single item that you have not received, as a result of issues relating to transfer overseas of information under the Data Protection Act, does not change this or justify your statement."

"To date, we have not seen sufficient documentation to prove IIIR has rights to Gmail," Nicole Wong, Google's associate general counsel, told Times Online.

"Nevertheless, we've tried to resolve this with them amicably. Unfortunately, it appears to us that their primary objective is money, rather than resolving this matter. Trying to use the media, rather than provide the necessary information, is not an indication of good faith discussions. It would be more productive to simply provide the necessary information."

Mr Smith, when contacted, decline to comment.

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