Reacting to the news that a key provision of the Affordable Care Act would be delayed by the Obama administration, Sen. Lamar Alexander described the landmark law as "unraveling."

The administration announced late Thursday that a requirement of the new health law, expected to be implemented in 2014, would be delayed for a year. Employers at companies with 50 or more workers would have been required to provide health coverage for their employees or pay a penalty to the government of $2,000 per employee. 

The provision, known as the employer mandate, has been delayed until 2015. According to a Wall Street Journal report, some companies had already cut back on workers' hours in order to avoid paying penalties for not providing coverage. 

Republicans, united in opposition to the law, quickly seized on the delay, offering new lines of criticism on the policy. 

In a news release, Alexander, the ranking Republican on the Senate committee that oversees health policy, offered a new denouncement of the bill he has opposed in recent years.

"Pushing the implementation of the employer mandate until after the 2014 election confirms the law was a historic mistake," Alexander said. "It should be repealed and replaced with effective legislation that will reduce costs by involving patients in health care decision-making. This delay will make a giant mess of the individual mandate because presumably individuals are still required to purchase insurance."

The Affordable Care Act was approved and signed into law in 2010.