WASHINGTON - More people applied for U.S. unemployment benefits last week, although jobless claims continue to be close to pre-recession levels.

Weekly applications for unemployment aid climbed 21,000 to a seasonally adjusted 311,000, the Labor Department said Thursday. The prior week's was revised up slightly to 290,000.

The four-week average, a less volatile measure, rose 2,000 to 295,750. That continues to be close to averages that predate the beginning of the recession in late 2007.

"Stepping back from the weekly volatility," said Jennifer Lee, senior economist at BMO Capital Markets, "the trend is still very encouraging and points to continued job growth."

Applications are a proxy for layoffs. When fewer employers shed workers, it suggests potentially rising incomes, increased hiring activity and confidence that the economy is improving.

Employers are searching for more workers.

In June, they advertised the most monthly job openings in more than 13 years, the government reported Tuesday. Employers posted 4.67 million jobs that month, up 2.1 percent from May's total of 4.58 million, according to the Labor Department. The number of advertised openings was the highest since February 2001, suggesting that hiring should continue to be solid in the coming months.

Still, the openings report showed that the hiring rate has not risen over the past year as quickly as the number of positions being advertised.

Job openings have increased 17.6 percent during the past 12 months, while hiring has risen 9.3 percent during the same period.

Yet the monthly net job gains have been solid in the past six months.

Employers added 209,000 jobs in July, the sixth straight month of job gains above 200,000. The economy has now produced an average 244,000 jobs a month since February.

The recent spurt of hiring has encouraged more people to start looking for work, causing the unemployment rate to inch up to 6.2 percent from 6.1 percent. The government only counts people searching for jobs as unemployed.

Hiring has yet to boost wages by much. Wage growth has slightly outpaced inflation since the recession ended more than five years ago.

But the greater the number of people with jobs, the greater the total number of paychecks, which could drive consumer spending and growth.