The Federal Open Market Committee has revealed that it was "broadly comfortable" to cut back on the Federal Reserve's $US85 billion per month bond-buying operation but there were few clues on when it could happen.

Key PNG commodities are treading water with the exception of nickel.

Singapore Tapis crude closed at $US116.04 a barrel overnight. This was a mere 0.3% increase from last Friday.

London Metal Exchange cash copper closed at $7292 a tonne overnight. While still in high ground, this was a 1% fall from last Friday.

By the same time comparison LME spot nickel was down by almost 4% to $14,358.5 a tonne overnight.

This morning Macquarie Private Wealth said it still found no grounds for optimism about the short term market outlook for nickel prices.

"Latest International Nickel Study Group data, as well as published stocks and our own analysis, confirm that the market remains in significant surplus for the time being," MPW said.

Spot gold is trading around $1378 an ounce in the past hour - relatively unchanged in percentage terms when compared to last Friday's close.

Key gainers this week included Bougainville Copper and St Barbara Corporation while InterOil's has lost less than 7% this week despite the news that the exclusivity arrangements have lapsed for its ongoing talks with ExxonMobil in PNG.