The National Party caucus has elected parliament's youngest MP, Jami-Lee Ross, to the position of "third whip", putting the finishing touches on Prime Minister John Key's cabinet reshuffle.

Traditionally a step towards cabinet, the three whip appointments have gone to Taupo MP Louise Upston, who moves up from junior to senior whip after previous senior whip Michael Woodhouse, who became a minister outside cabinet in last week's reshuffle in which two senior Ministers' heads rolled.

The new junior whip will be MP for Hamilton West, Tim Macindoe, and Mr Lee-Ross, the MP for Botany, has been appointed to the newly-created position of third whip, which is allowed for parties with more than 45 MPs.

Aged 27, Lee-Ross was the youngest MP in parliament when he won the 2011 byelection for the Botany electorate after the resignation of sitting MP Pansy Wong.

Mr Macindoe is a former prinicipal at the Anglican private school St Peter's College and has served as a deputy chairman on select committees.

(BusinessDesk)