San Francisco  - California Governor Arnold Schwarzenegger vowed Wednesday to take "swift action" against his wife, Maria Shriver, who was caught three times by paparazzi talking on her cell phone while driving, in violation of a law signed by her husband.

Shriver, a scion of the Kennedy political clan, was portrayed in a 17-second video by celebrity website TMZ. com talking on her cellphone on three different occasions dating back to June, with the latest incident recorded on Tuesday.

Schwarzenegger last year signed into law a measure banning the use of handheld communication devices while driving. Fines are 20 dollars for the first offence and 50 dollars for subsequent violations, but enforcement has generally been lax throughout the state.

Schwarzenegger vowed, however, to get tough with his wife.

"Thanks for bringing her violations to my attention," the former action movie star said in a Twitter message to TMZ editor Harvey Levin. "There's going to be swift action."

Shriver later apologized for the gaffe and vowed to donate the cellphone she had used illegally to a programme that helps domestic violence shelters.

"I'm sorry," she said in a statement. "I will be donating my favorite old cell phone. That's my version of swift action with a higher purpose." (dpa)