US telco giant AT&T has announced it’s following up the acquisitions of Iusacell and Nextel with a further investment of $3 billion over the next three years to improve its mobile network in Mexico.

“We are building a network in Mexico that is capable of bringing innovation and economic vitality to the country, just as we have done in the U.S.,” said AT&T CEO Randall Stephenson. “We plan to deliver high-quality, high-speed mobile Internet service to Mexico, creating the first-ever North American Mobile Service Area covering 400 million people and businesses in Mexico and the U.S.

“Reforms introduced by President Peña Nieto, with support from the Mexican Congress and IFETEL, have given us the ability to invest in building an advanced mobile network in Mexico…The mobile Internet in the U.S. created an engine of economic growth. As we extend it into Mexico, we believe it will do the same here.”

The first phase of the roll-out is expected to complete by the end of this year, covering 40 million Mexicans out of a total population of around 120 million. The number of people covered is expected to hit 75 million by the end of next year and 100 million by the end of 2018.

As part of its trans-continental vision AT&T is also going to introduce a roaming feature from next month that allows its Mexican customers to make calls and use data on AT&T in the US. This is being positioned as a free extension to existing plans and will include things like Google Play billing.

Much of the AT&T announcement focused on how committed to the people of Mexico AT&T is, so presumably the company is still anxious to stay on the right side of regulators and politicians. There’s even an initiative called ‘Nuestra Promesa’ (our promise), which is a general quality of service statement of intent, and various other pseudo-philanthropic ventures.