LOS ANGELES — President Barack Obama on Monday waded into the labor standoff in Wisconsin and warned that the rights of public employees should not be infringed upon.

Speaking to the National Governors Association, Obama noted that many states as well as the federal government face tough economic choices. But the president, who has been criticized by some labor allies for not speaking out more forcefully on the Wisconsin situation, noted the fight between Wisconsin’s public unions and the Republican administration in Madison.

“”I don’t think it does anybody any good when public employees are denigrated or vilified or their rights are infringed upon,”” Obama said in televised remarks. “”We need to attract the best and brightest to public service. These times demand it.””

Wisconsin Gov. Scott Walker has proposed increasing the amount of money that public employees would have to pay for health care and pension benefits. The Republican governor has also sought to limit collective bargaining rights for most public employees.

The plans, which have passed the Wisconsin Assembly, are stalled in the state Senate, whose 14 Democrats have fled to Illinois, making it impossible to have a quorum.

On Monday, Walker gave the Democrats 24 hours to return. He said if his proposals weren’t passed, the state would be unable to finance part of its debt, leading to some layoffs.