Hardy Underwriting has told Omega to make its bid by 1 August or back off.
Hardy issued a 'put up or shut up' statement on the stock exchange this week saying: "The board believes the Takeover Panel's announcement should help to ensure that the company is not subject to a prolonged period of potentially damaging uncertainty, which the board does not believe would be in the interests of company shareholders."
Hardy also confirmed that three of the insurer's major shareholders, which do not have an interest in Omega and make up roughly 29% of the company, are "not minded to accept an offer" on the present terms.
According to Omega sources, this means if the share offer were raised then the merger could go ahead.
