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Dec 12 (Reuters) - Australian shares ended Monday flat with an upside bias, after hitting their highest in four months in early trading, underpinned by oil and gas stocks.
The energy index .AXEJ jumped to its highest since Oct. 12, 2015, after oil prices rose to the highest in a year and a half high on Monday, after OPEC and non-OPEC producers agreed to cut oil output. O/R
Majors Oil Search OSH.AX and Woodside Energy WPL.AX both rose more than 3 percent.
The S&P/ASX 200 index .AXJO ended 2.2 points or 0.04 percent higher at 5560.6, its highest close since Aug 1, after surrendering some early session gains as investors turned their attention to an interest rate hike expected from the Federal Open Market Committee meeting this week.
Financials added gains, with three of the "Big Four" banks up. ANZ Bank ANZ.AX ended 0.3 percent lower.
Exchange operator ASX Ltd ASX.AX shed 0.2 percent, while Seven West Media SWM.AX rose 0.7 percent to its highest in two months.
Large cap grocer Woolworths WOW.AX slipped 0.3 percent. Its rival, Wesfarmers Ltd WES.AX , ended in positive territory.
New Zealand's benchmark S&P/NZX 50 index .NZ50 slipped 0.25 percent or 17.26 points, to finish the session at 6876.04, hurt by consumer staples.
A2 Milk ATM.NZ was the biggest loser on the index, ending the session down 5 percent.
But Fonterra Co-Op FCG.NZ , the world's biggest dairy exporter, however, gained 0.17 percent after it confirmed a forecast farmgate price of NZ$6 per kilogram.