National MPs have agreed to a conscience vote on raising the age when people can buy alcohol.
The Government is preparing to release its proposals for reforming the liquor laws.
At caucus on Tuesday, National MPs agreed to support the whole package of measures with a party vote, including transport safety measures that include a zero drink drive limit for drivers under the age of 20.
However, National MPs will be free to chose how to vote on the purchase age.
The Government has not yet spelled out its recommendation.
However, Prime Minister John Key has said he favours a split age, allowing people to buy alcohol at licensed premises at 18, but waiting until they are 20 to purchase at an off licence.
Labour leader Phil Goff says he favours a split purchase age too, and Labour MPs will also be free to chose how to vote on the issue.
