* Brent up 1.4 pct this week to near $116 on Middle East unrest
* TECHNICALS: Brent is temporarily neutral
* Coming Up: U.S. GDP for fourth quarter; 1230 GMT (Adds context on Yemen protests, rising summer demand)
By Alejandro Barbajosa
SINGAPORE, March 25 (Reuters) - Brent crude was steady near $116 on Friday ahead of protests planned in Yemen and Bahrain, heading for a third straight weekly gain and up 1.4 percent since western powers last weekend launched a military campaign in Libya.
Brent crude for May shed 15 cents to $115.57 a barrel at 0837 GMT, about $4 from a 2-1/2-year high near $120 a month ago, while U.S. crude fell 20 cents to $105.40.
After the first rounds of a U.N.-backed offensive to disable Libya's air defences and prevent Muammar Gaddafi's forces from launching attacks on civilians, NATO said it would enforce a no-fly zone over the country but stopped short of taking full command.
Libyan oil exports of about 1.3 million barrels per day (bpd) have virtually vanished, eroding spare capacity as Saudi Arabia and other OPEC members increased production and raising concern the group may struggle to fill bigger disruptions.
"So long as ongoing problems in the Middle East continue to elevate risks of a further supply disruption, there is a strong likelihood of a price spike in the second quarter as the market demands additional oil to meet summer demand," said J.P. Morgan analysts headed by Lawrence Eagles.
The bank on Friday raised its forecast for Brent in the second quarter to $118 from $105, saying "dips in volatility, like the one that we saw this week, appear to offer good entry points for hedging strategies."
Barclays Capital also raised its projection for 2011 Brent to $112 from $91.
Concerns about Portugal's sovereign debt have slowed oil price gains this week, after the country's prime minister resigned on Wednesday, falling victim to the European Union's rolling financial crisis and prompting Standard & Poor's to downgrade the credit ratings for the nation.
European leaders agreed on Thursday to increase their financial rescue fund to the full 440 billion euros by June.
Trading volumes in oil futures markets have been thin this week as investors await the next turn of events in the Middle East and weigh developments around Japan's nuclear crisis.
MIDDLE EAST
Allied warplanes hit military targets deep inside Libya on Thursday but failed to prevent tanks re-entering the western town of Misrata, underlining the difficulty of the mission to protect Libyans from government forces.
"If we assume that Libya's 1 million barrels a day of exports has been more or less replaced by Saudi production (leaving aside crude qualities for the moment) this means that output from the Middle East is relatively unchanged," said Edward Meir, senior commodity analyst at brokers MF Global.
In Yemen, the opposition stepped up efforts to remove President Ali Abdullah Saleh on Thursday, dismissing his offer to stand down after a presidential election at the end of the year.
Protesters planned a March 25 "Friday of Departure" rally in a country that sits near shipping lanes that skirt the Arabian peninsula and from where al Qaeda has attempted attacks on Saudi Arabia.
In Bahrain, a small island country that lies less than 100 kilometres from the hub of the Saudi Arabian oil industry, opposition activists said they planned to hold a day of demonstrations on Friday in defiance of a ban on all public gatherings.
At least 37 people were killed in the city of Deraa in Syria on Thursday as protests grew.
Oil prices will stay above $100 a barrel through 2013, a Reuters poll showed on Thursday, as analysts sharply revised their forecasts on expectations of a protracted outage in Libya and uncertainty about the Middle East and North Africa, which combined produce more than a third of the world's oil.
J.P. Morgan says additional supplies are required from the Organization of the Petroleum Exporting Countries in the run-up to northern hemisphere summer demand, before the group's next meeting in June.
"By then, it will be too late to prevent higher prices and could extend what we see as a mid-quarter blip to a much more serious and destabilizing price surge that could distort stock-holding behavior and economic growth," the bank said.