U.S. news media are reporting that President Barack Obama plans to seek congressional approval for a $300 billion proposal to boost the country’s lagging economy through a variety of tax cuts, aid for unemployed workers and construction spending.

The president is set to unveil the plan Thursday night in a speech to a joint session of Congress, but government officials this week have been divulging some of the details. News accounts say Mr. Obama wants to renew financial assistance for workers who have been unemployed for extended periods. Earlier this week, the president said he wants to extend for a year the 2 percent payroll tax cut for all workers that is set to expire at the end of this year.

In addition, the president plans to seek approval for the same tax cut for employers, and add a tax credit for companies that hire more workers. Mr. Obama also plans to call for new spending to fix the country’s aging and crumbling roads, bridges and schools.

The Democratic president’s plan is likely to meet with considerable opposition from Republican lawmakers who are opposed to increased spending by the debt-ridden government. In advance of the speech, some Republicans say that the proposals represent a reprise of his failed economic policies.

The country’s economy has virtually stalled, growing at a slow pace, and last month added no new jobs. About 14 million workers are unemployed and millions more are working part-time or in jobs they consider below their skill level.