Dunkin' Brands Group (DNKN), parent of Dunkin' Donuts and Baskin-Robbins ice cream outlets, reported lower-than-expected quarterly results as extreme cold weather in parts of the United States hit comparable-store sales growth.

Sales at established Dunkin' Donuts outlets in the United States rose 1.2% in the first quarter, the company said on Thursday. Analysts polled by Consensus Metrix had expected an increase of 3.4%.

"We had a difficult first quarter with our comparable-store sales growth in the U.S. significantly impacted by severe weather in the regions of the country where most of our Dunkin' Donuts restaurants are located," Chief Executive Nigel Travis said in a statement.

Dunkin' Donuts domestic coffee shops account for about 75% of the company's total sales.

"We estimate weather contributed approximately 200 basis points of negative impact (on traffic growth) in the quarter," the company said.

Top U.S. rival McDonald's (MCD) said this week sales at U.S. restaurants open at least 13 months fell a steeper-than-expected 1.7% in the first quarter, when its prices rose and traffic fell.

Dunkin's net income fell to $23 million, or 21 cents per share, in the quarter ended March 29, from $23.8 million, or 22 cents per share, a year earlier.

Excluding items, the company earned 33 cents per share. Analysts on average had expected 36 cents per share, according to Thomson Reuters I/B/E/S.

Revenue rose 6.2% to $171.9 million but fell short of the average analyst estimate of $172.2 million.

Dunkin' Brands reaffirmed its profit forecast for the year.

The shares are off by about 1.7% Thursday at $46.77.