Sprint Nextel, the US mobile operator formed last week in a $36bn merger, aims to focus on its domestic network but will keep an eye out for expansion opportunities abroad.

Gary Forsee, president and chief executive of the wireless group, said he wanted it to “be the best wireless company in the United States” but that he would “take a look” at any opportunities for international expansion.

Mr Forsee was speaking after he rang the opening bell at the New York Stock Exchange to mark the start of trading in the merged company.

The merger between Sprint and Nextel was announced last December and follows a round of consolidation in the US wireless market, one of the fastest-growing segments of telecommunications. The biggest groups are Verizon Wireless and Cingular.

Sprint Nextel is spinning off its local businesses to shareholders to focus on the wireless business. Mr Forsee said he expected this to make Sprint Nextel a top choice in partnerships with content companies and other groups.

Together with Tim Donahue, executive chairman, Mr Forsee said merger plans were much more advanced then he had experienced in previous mergers. One remaining obstacle was the need to buy or settle with affiliates, and he said talks had begun with Nextel Partners and others.

Sprint Nextel, which is using yellow as its brand colour, expects to start offering its new products to consumers from September. The group will also next month reveal more details and the planned $12bn in synergies the merger is expected to achieve as well as its planned capital structure.

Mr Forsee and Mr Donahue, who used to head Sprint and Nextel respectively, said their close working relationship and shared vision of the future had helped push integration plans.

The two executives have talked to many customers over recent months and said there was demand for products that could be used at work, at home and on the go. “We have a vision of a combined service,” Mr Forsee said.