Virgin Radio owner Scottish Media Group (SMG) has rejected a revised merger proposal from Ulster Television (UTV).
UTV first approached SMG earlier this month
SMG said UTV was now offering SMG shareholders 52% of the joint company, rather than a 50:50 split.
However, SMG did not entirely close the door on any further offers, saying it was prepared to meet UTV to discuss a merger on mutually acceptable terms.
Both firms have major radio interests. Last year UTV bought the Wireless Group which includes TalkSport.
SMG also owns the Scottish Television Group (STV), cinema advertising business Pearl & Dean and TV production firm Ginger Productions.
Takeover speculation surrounding the two firms has been rife in recent weeks.
Earlier this month, reports suggested former Channel Four executive Rob Woodward was putting together a cash offer for SMG.
Meanwhile, further reports have said that UTV is awaiting a counterbid from SMG.
Experts said a lack of cash in the UTV proposal would put off many SMG shareholders, given UTV is worth about £40m less than the Glasgow-based group.