The head of US number three wireless carrier Sprint on Tuesday touted consolidation for the US mobile industry, but declined to comment on a potential tie-up with T-Mobile USA. Sprint chief executive Dan Hesse said he had argued for some time that industry consolidation -- excluding leaders  AT&T and Verizon -- "would be better for the country and better for consumers."   "And I still believe that's very much the case," he told analysts on a conference call. Hesse declined to comment on specific potential transactions, including reports that Sprint is considering a bid for number four T-Mobile. Sprint has received preliminary financing offers worth some $30 billion for a T-Mobile purchase. But US regulators have discouraged the deal, press reports said. US antitrust authorities in 2011 blocked number two carrier AT&T's takeover of T-Mobile, which is majority owned by Deutsche Telekom. But US regulators have green-lighted some smaller transactions, including Japanese technology investor SoftBank's purchase last year of Sprint, and the merger of T-Mobile with smaller rival MetroPCS. Verizon also saw no resistance to its purchase of Vodafone's stake in its Verizon Wireless joint venture. A merger between Sprint and T-Mobile would allow it to close the competitive gap in terms of subscriber base. AT&T and Verizon each have more than 100 million subscribers. Sprint said Tuesday it finished 2013 with 53.9 million subscribers, while T-Mobile reported 45 million subscribers at the end of September.