President Obama on Tuesday vetoed a measure passed by the Republican-run Congress blocking the National Labor Relations Board from streamlining the process for union elections, saying government should not make it harder for workers to be heard in the workplace.

Obama also announced a fall White House summit on worker rights.

The NLRB rule, set to take effect on April 14, would shorten the amount of time between when an election is called and when it is held by eliminating a 25-day waiting period.

Republicans and business groups opposed the rule, arguing that it would limit the ability of businesses to prepare for what some critics have dubbed "ambush elections." Opponents also said workers wouldn't have enough time to make informed decisions about whether to join a union.

In the Oval Office on Tuesday, Obama called the labor board's changes "common sense" and "modest" before he vetoed a resolution the Congress passed to nullify the rule.

"Unions historically have been at the forefront of establishing things like the 40-hour work week, the weekend, elimination of child labor laws, establishing fair benefits and decent wages," Obama said. "And one of the freedoms of folks here in the United States is, is that if they choose to join a union, they should be able to do so. And we shouldn't be making it impossible for that to happen."

House Speaker John Boehner, R-Ohio, criticized Obama's decision.

"The NLRB's ambush election rule is an assault on the rights and privacy protections of American workers," Boehner said. "With his veto, the president has once again put the interests of his political allies ahead of the small-business owners and hardworking Americans who create jobs and build a stronger economy."

The rule was a victory for unions, which have long complained that the process is too long.

AFL-CIO President Richard Trumka, using language similar to Obama, has said that the board's "modest but important reforms" will help reduce delays and make it easier for workers to vote on forming a union. Using language similar to Boehner, Trumka has called lawmakers' attempt to overturn the rule "a direct attack on workers and their right to be heard in the workplace."

The NLRB rule also permits some documents to be filed electronically instead of by mail, and generally delays legal challenges by employers until after workers have voted on whether to unionize. The rule will also require employers to supply union organizers with workers' email addresses and telephone numbers.