AT&T Inc. posted a 22 percent rise in first-quarter net income on Tuesday, as strong growth at the company's wireless operations made up for its weakness in its traditional wireline business.

The nation's largest telecommunications company earned $3.5 billion, or 57 cents a share, compared with $2.85 billion, or 45 cents a share, in the same quarter a year earlier. The results were in line with expectations of analysts polled by Thomson Financial.

In morning trade, the stock was trading 0.8 percent higher at $37.87.

The results include severance charges related to layoffs in AT&T's declining landline business and acquisition-related expenses. Earnings were reduced by $1.2 billion in noncash charges related to its various mergers and $374 million in costs related to its recent layoffs, the company said. Revenue climbed 6.1% to $30.74 billion.

AT&T's revenue grew 6.1 percent from a year ago to $30.7 billion, but that growth covered a shift within the company's business lines.

Revenue from its wireline voice service dropped 7.1 percent to $9.7 billion, while wireless revenue increased 17.1 percent to $10.6 billion. The exclusive U.S. carrier for Apple Inc's iPhone, said it increased its wireless subscribers by 1.3 million in the quarter. Meanwhile, data revenue grew more slowly, rising 6 percent to $6.2 billion.

Both AT&T and rival Verizon Communications Inc are relying on mobile phone sales for growth as traditional home phone users continue to decline.

The San Antonio-based company CEO, Randall L. Stephenson, said the carrier will continue to seek ways to cut costs and focus its business on its wireless and data services.

Revenue growth continues to ramp, we have good momentum across key growth areas, major cost initiatives are on track, and our operational results reinforce the confidence we have in our outlook, Mr. Stephenson said in a statement.