Arnstad was born in Stjørdal. She held various jobs and offices before entering politics on a national level in 1993. That year, she was elected to the Storting and sat as a representative for the Centre Party from 1993 to 1997. Following the 1997 election, she took a seat in Kjell Magne Bondevik's first Cabinet as Minister of Petroleum and Energy from 17 October 1997 to 17 March 2000, when the government resigned over the issue of gas power stations. In 2001 she was once again elected to the Storting, where she sat until 2005.
After the Norwegian parliamentary election of 2005, she was mentioned by many as a possible minister in the new government that included the Centre Party, but Arnstad did not become a minister at that time. In 2012, she became the Minister of Transport in Stoltenberg's Second Cabinet.
She is nominated at the top spot on the Centre Party ballot in Nord-Trøndelag for the Norwegian parliamentary election, 2013, which is considered a safe seat. She was preferred for the top spot over Lars Peder Brekk who had the position in 2005. She has been mentioned as a possible future leader of the Centre Party.
|Norwegian Minister of Petroleum and Energy