SAN FRANCISCO (AP) — Comcast CEO Brian Roberts says the company is moving “full steam ahead” with its proposed $45 billion acquisition of Time Warner Cable despite the uncertainty raised by President Barack Obama’s call for tougher regulations on high-speed Internet service providers.

As part of its commitment to getting the Time Warner deal done, Roberts says Comcast Corp. still intends to spend about $20 billion during the next two years to improve its Internet service and other products.

Roberts’ stay-the-course remarks, made during a presentation Wednesday in San Francisco, contrasted with a cautionary statement from AT&T’s CEO Randall Stephenson. In earlier appearance at an investment conference, Stephenson said AT&T Inc. is scaling back on its spending plans until the Federal Communications Commission determines the new rules governing Internet service providers.