New York: Julie Bishop has revealed she and Kevin Rudd became close friends as a result of Labor's leadership wars and has suggested the Opposition's Foreign Affairs spokeswoman, Tanya Plibersek, is a lightweight on foreign policy compared to the former Labor prime minister.

In an exclusive interview with Fairfax Media, the Minister for Foreign Affairs says she consulted Mr Rudd on policy issues in opposition and the pair still text each other about foreign policy.

The pair entered politics together in 1998 but first became friendly when they observed Zimbabwe's election together in 2002.  They have stayed in touch ever since but Ms Bishop said they developed a "much closer friendship" as a result of Labor's bitter leadership battles.

"Through some of the really difficult times for him, I would go around and see him, he would come around and see me, we talked a lot about foreign policy, We talked a lot of about different approaches, I ran ideas past him," Ms Bishop said.

"He knew that the Opposition had taken a position from 2007 on the Security Council and we would discuss it quite openly," she said.