(Updates with delivery of Austin remarks)

WASHINGTON, April 30 (Reuters) - The United States needs to prepare for a potential future conflict bearing little resemblance to "the old wars" that have long consumed the Pentagon, Defense Secretary Lloyd Austin said Friday in his first significant policy speech.

Austin called for harnessing technological advances and better integrating military operations globally to "understand faster, decide faster and act faster."

"The way we fight the next major war is going to look very different from the way we fought the last ones," Austin said during a trip to the Hawaii-based U.S. Pacific Command.

Austin did not explicitly mention rivals like China or Russia. But his remarks came as the United States starts an unconditional withdrawal from Afghanistan on orders from President Joe Biden aimed at ending America's longest war and resetting Pentagon priorities.

Austin acknowledged that he has spent "most of the past two decades executing the last of the old wars."

Critics say withdrawing from Afghanistan will not end the Asian country's internal conflict, extinguish the threat of terrorism or make experience from 20 years of counter-insurgency warfare irrelevant, as militant organizations like Islamic State spread around the world.

Austin's remarks did not appear to prescribe specific actions or predict any specific conflict. He instead appeared to outline broad, somewhat vague goals to drive the Pentagon under the Biden administration.

"We can't predict the future," Austin said. "So what we need is the right mix of technology, operational concepts and capabilities - all woven together in a networked way that is so credible, so flexible and so formidable that it will give any adversary pause."

Preventing a conflict would mean creating "advantages for us and dilemmas for them," he said.

U.S. responses could be indirect, he said, outlining a scenario in which cyber warfare could be used "to respond to a maritime security incident hundreds of miles away." (Reporting by Phil Stewart; Editing by David Gregorio and Leslie Adler)