Oil markets have started the new year with a bang as optimism about global demand coincides with renewed supply concerns, fuelling a fresh batch of bets for the energy commodity to hit $US100 a barrel this year.

Brent crude rallied 5 per cent in the opening week of 2022, and has now entirely retraced the heavy losses it suffered in early December when omicron threatened to create havoc on demand through the potential reintroduction of mobility restrictions around the globe.