In an announcement that could boost competition with incumbent providers such as Comcast and AT&T, Google Fiber said it’s exploring an expansion that would bring its 1-Gig and pay TV services to Chicago and Los Angeles.

Google Fiber has invited authorities in those cities to explore the idea after the provider refined its buildout checklist.

“Now, we’re ready to use that same process to work with two of the biggest cities in the country, Jill Szuchmacher, director of Google Fiber expansion, said Tuesday in this blog post. "Home to a combined 6+ million people, Chicago and L.A. are the two largest metros we’ve engaged with to date.”

The exploration and reach out with those cities are a “big step” in the process, she added, but noted that there’s no guarantee that Google Fiber will launch in Chicago and/or L.A.

But if it does, it will amp up competition in those markets.

In L.A., Google Fiber would come up against Time Warner Cable, the area’s primary MSO incumbent that’s merging with Charter Communications, and AT&T, which recently identified Los Angeles as an expansion site for its fiber-fed GigaPower platform. In June, the city of Los Angeles approved a request for participants (RFP) as part of the CityLinkLA project to identify one or more providers to commit to deploying wireline and WiFi networks that can deliver speeds of 1 Gbps, and complete the job within the next five years.

In Chicago, Google Fiber would tangle with overbuilder RCN, and Comcast, which has introduced its 2 Gbps “Gigabit Pro” FTTP offering in the Windy City. AT&T has also launched GigaPower to parts of Chicago.

Google Fiber currently offers service in three markets – Kansas City; Provo, Utah; and Austin, Texas; and has buildouts underway in Salt Lake City, San Antonio, Nashville, Atlanta, Raleigh-Durham and Charlotte.

Google Fiber’s also exploring buildouts in Portland, Ore.; San Jose, Irvine and San Diego, Calif.; Phoenix, Ariz.; Oklahoma City; Louisville, Ky.; and Jacksonville and Tampa, Fla.

Google Fiber has not released subscriber counts for its gigabit broadband and pay TV services, but Bernstein Researchestimated recently that it has between 100,000 to 120,000 paid subs, and that its network currently passes about 427,000 homes and 96,000 business locations.