LVRs restrict how much banks can lend to low-deposit borrowers.
Under the previous LVR rules banks were only able to do 5 per cent of new lending to investors with a deposit of under 30 per cent.
Westpac has said it never changed its lending settings and they remained in line with previous LVR rules.
"We have remained open for business across all segments and have grown our support for housing, agri and business customers over the past year," a spokesperson said.
Booming house prices in the past two months have put the Government and Reserve Bank under pressure to act, with many blaming low interest rates for the latest surge.
Earlier today Finance Minister Grant Robertson revealed he had written to the Reserve Bank asking it to consider house prices more closely in its monetary policy remit.
LVRs and fall under the Reserve Bank's financial stability remit.
Tomorrow the RBNZ will deliver its latest Financial Stability Report which will include an assessment of how much risk it sees in current levels of mortgage debt.