WASHINGTON (Reuters) - U.S. health officials aim to move swiftly and clearly to implement newly enacted healthcare reforms, health secretary Kathleen Sebelius said on Tuesday in remarks aimed at selling Americans on the benefits of the controversial changes.

National and state regulators will also keep a close eye on private health insurance companies to ensure that they comply with new rules, Sebelius said in a speech.

"For years, Americans have struggled with a health insurance system that was opaque, unnecessarily confusing, and often overwhelming to navigate," she told the National Press Club. "Our goal as we implement this law is to be the opposite of that -- to be as clear and transparent as possible."

Calling the U.S. Health and Human Services Department "a nationwide health insurance reform help desk," Sebelius pledged to help consumers wade through the new reforms passed by the Democratic-controlled Congress.

The law requires people to purchase a health insurance policy or pay a fine, and provides subsidies to help those who could not afford coverage on their own. Overall, it aims to insure an additional 30 million Americans.

"We know that the only way this law will achieve its full potential is if Americans understand and take advantage of all the new benefits and choices that will be available to them," Sebelius said.

Republicans and other critics say the insurance mandate is unconstitutional and are pushing back against the new law through lawsuits and other means.

Sebelius said the Obama administration was "confident that the law is on solid, constitutional ground."

NO CHERRY-PICKING

While Sebelius

acknowledged much work remains to educate Americans about the many provisions tucked in the 2,400-page healthcare law signed by President Barack Obama last month, she said the goal was to help empower consumers.

Her department will set guidelines to boost competition in the health insurance market and "serve as an umpire to make sure insurance companies treat Americans fairly," she said.

"Working with the insurers to actually look for ways that we develop a new business model... is going to require oversight and vigilance," Sebelius said.

"It means changing the rules," she added, noting that companies will have to compete for new business based on prices and "not basing their customer selection on cherry-picking the market and eliminating certain groups and individuals."

The law prohibits insurer practices such as denying coverage to people with pre-existing medical conditions.

Health insurers had lobbied hard against the bill. Robert Zirkelbach, a spokesman for America's Health Insurance Plans lobby group, said they were now focused "on implementing the new reforms in a manner that will minimize disruption for the more than 200 million people we serve."

But Sebelius said insurers stand to benefit from more business, ensuring cooperation with the law.

"The trade-off of having additional customers for the private market means that the new rules will be followed and will be vigorously enforced," she said.

Sebelius also warned about reports of scam artists trying to sell bogus health insurance policies and urged consumers and state regulators to be on alert.

(Additional reporting by Donna Smith; editing by Mohammad Zargham)