The new price estimate for 2011 Brent crude at $105 a barrel, up from $90 previously, assumes that the supply disruption continues into the second quarter and OPEC’s 5.2 million barrels per day (bpd) spare capacity is deployed effectively, Citigroup analysts said.

Citigroup also upped its 2011 WTI price forecast to $94 a barrel from $91.

Similarly, Citi raised its 2012 Brent estimate to $100 a barrel from $90, and for WTI to $95 from $91.

Brent crude is currently trading at $116.86 a barrel and WTI is at $105.95.

The analysts warned significant volumes above the estimated 3.3 million bpd of Middle East and North Africa exports could be affected by economic stress and political dissatisfaction of the masses there. To date, the political upheaval in that region has disrupted 1.3 million bpd of exports.

“The fear that the market’s spare cushion is compromised below 4 percent maintains a ‘disruption’ premium into 2011,” they said.