Starbucks has sued a former top executive, claiming he violated a non-competition agreement by going to work for competitor Dunkin' Donuts.

Paul Twohig, who had been in charge of Starbucks' retail stores in the southeastern U.S., left the company in March. He received a severance package after signing a separation agreement in which he promised to honor an earlier non-competition agreement that said he would not work for a Starbucks competitor for 18 months, according to a lawsuit filed Monday in U.S. District Court in Seattle.

Twohig, who did not return phone calls to his South Carolina home, asked Starbucks in August if he could be released from the agreement in order to work for Dunkin' Donuts, the lawsuit said.

Canton, Mass.-based Dunkin' has a large presence in the eastern U.S. and has had turnover at the top lately, including in a top branding position it appears Twohig was meant to partially fill.

Starbucks declined Twohig's request. At Starbucks, he had "participated in and was responsible for formulating business strategies to grow Starbucks business and respond to competitors, including Dunkin' Donuts," the lawsuit said.

In September, Dunkin's head of human resources and another former Starbucks employee, Christine Deputy, contacted the coffee company. Starbucks said it told her that Twohig was "not in a position to accept a position" at Dunkin'.

Within the past week, Starbucks learned through Internet searches that Twohig had apparently accepted a job as Dunkin's brand operations officer.

Starbucks asked that the court to bar Twohig from working at Dunkin' until the 18 months stipulated by non-competition agreement have passed, and that he not be permitted to share any of Starbucks' confidential information.

The chain also wants monetary damages, including but not limited to the amount Twohig received when he left the company.

Twohig worked for Starbucks from 1996 to 2002, then left and became chief operating officer of Panera Bread. When he returned to the coffee company in 2004, he signed the non-competition agreement, the lawsuit said.

Before joining Starbucks, he was a Burger King executive and franchisee and worked at Boston Market, according to news reports.