NEW: @KarlDBerkeley has announced his resignation as leader of the National Party.
From the National team, thank you for all your hard work, Karl!
A leadership contest will take place to determine the next leader later this week.
๐จ @KarlDBerkeley and the National team are working hard to get our country back on track.
Join us as we work to deliver for you โฌ๏ธ
https://t.co/4Rmme3uv9T