New $115 high for crude

Before the $115.54 WTI peak, ICE Brent for June delivery had earlier hit a new high of $113.38/bbl up $0.72 from Wednesday's close of $112.66/bbl.

Analysts also noted that the weak US dollar would enable crude oil to continue posting fresh highs.

"Investors have taken the developing US economic downturn as a signal that the Fed will continue to cut rates and that the dollar will continue to weaken," noted Michael Wittner, global head of oil research with French investment bank Societe Genera