Waymo said Thursday it will begin mapping and eventually testing its autonomous long-haul trucks in Texas and parts of New Mexico, the latest sign that the Alphabet company is expanding beyond its core focus of launching a robotaxi business.

Waymo said in a tweet posted early Thursday it had picked these areas because they are “interesting and promising commercial routes.” Waymo also said it would “explore how the Waymo Driver” — the company’s branded self-driving system — could be used to “create new transportation solutions.”

Waymo plans to mostly focus on interstates because Texas has a particularly high freight volume, the company said. The program will begin with mapping conducted by Waymo’s Chrysler Pacifica minivans.

The mapping and eventual testing will occur on highways around Dallas, Houston and El Paso. In New Mexico, Waymo will focus on the southern most part of the state.

Interstate 10 will be a critical stretch of highway in both states — and one that is already a testbed for TuSimple, a self-driving trucking startup that has operations in Tucson and San Diego. TuSimple tests and carries freight along the Tucson to Phoenix corridor on I-10. The company also tests on I-10 in New Mexico and Texas.

This week, we’ll start driving our Chrysler Pacificas and long-haul trucks in Texas and New Mexico. These are interesting and promising commercial routes, and we’ll be using our vehicles to explore how the Waymo Driver might be able to create new transportation solutions. pic.twitter.com/uDqKDrGR9b — Waymo (@Waymo) January 23, 2020

Waymo, which is best known for its pursuit of a robotaxi service, integrated its self-driving system into Class 8 trucks and began testing them in Arizona in August 2017. The company stopped testing its trucks on Arizona roads sometime later that year. The company brought back its truck testing to Arizona in May 2019.

Those early Arizona tests were aimed at gathering initial information about driving trucks in the region, while the new round of truck testing in Arizona marks a more advanced stage in the program’s development, Waymo said at the time.

Waymo has been testing its self-driving trucks in a handful of locations in the U.S., including Arizona, the San Francisco area and Atlanta. In 2018, the company announced plans to use its self-driving trucks to deliver freight bound for Google’s data centers in Atlanta.

Waymo’s trucking program has had a higher profile in the past year. In June, Waymo brought on 13 robotics experts, a group that includes Anki’s co-founder and former CEO Boris Sofman, to lead engineering in the autonomous trucking division.