WASHINGTON  President Obama said Saturday that Americans would see immediate benefits from a landmark overhaul of the nation’s health insurance system and he urged Congress to swiftly reconcile differences over the legislation so it could be signed into law in the coming weeks.

“Once I sign health insurance reform into law, doctors and patients will have more control over their health care decisions, and insurance company bureaucrats will have less,” Mr. Obama said. “All told, these changes represent the most sweeping reforms and toughest restrictions on insurance companies that this country has ever known.”

In his weekly Saturday address, Mr. Obama highlighted elements of the plan that would take effect soon after enactment of the bill. He said the law would allow people with pre-existing illnesses to be able to buy affordable insurance, children with pre-existing conditions would no longer be denied coverage and small business owners who could not afford to cover employees would receive tax credits to buy insurance.

“What every American should know is that once I sign health insurance reform into law, there are dozens of protections and benefits that will take effect this year,” Mr. Obama said.