* Major oil exporters Nigeria, Venezuela in crisis

* U.S., China output also down sharply

* High inventories help compensate - Morgan Stanley

* Renewed Canadian output, rising OPEC supplies also weigh

* Looming refinery glut could spill back into crude

(Adds comment, refinery outlook, updates prices)

By Henning Gloystein

SINGAPORE, May 16 (Reuters) - Oil prices jumped over 1 percent on Monday after long-time bear Goldman Sachs said the market had ended almost two years of oversupply and flipped to a deficit following global oil disruptions.

Brent crude futures LCOc1 were trading at $48.47 per barrel at 0703 GMT, up 64 cents, or 1.3 percent, from their last settlement.

U.S. crude futures CLc1 were up 62 cents, or 1.3 percent, at $46.83 a barrel.

Supply disruptions around the world of as much as 3.75 million barrels per day (bpd) have wiped out a glut that pulled down oil prices by as much as over 70 percent between 2014 and early 2016. urn:newsml:reuters.com:*:nL5N18A5CU

The disruptions have now triggered a U-turn in the outlook of Goldman Sachs, which long warned of overflowing storage and another looming price crash. urn:newsml:reuters.com:*:nL5N18D035

"The oil market has gone from nearing storage saturation to being in deficit much earlier than we expected," Goldman said.

"The market likely shifted into deficit in May ... driven by both sustained strong demand as well as sharply declining production," it said, flipping the market from a 2 million bpd in 2015 supply overhang to a deficit of over 400 million bpd by the fourth quarter this year.

However, Goldman cautioned that the market would flip back into a surplus of 258-403 million bpd in the first half of 2017.

In Nigeria, output has fallen to its lowest in decades at around 1.65 million bpd following several acts of sabotage. urn:newsml:reuters.com:*:nL5N18C0LG urn:newsml:reuters.com:*:nL3N18A34L

In the Americas, Venezuela seemed on the brink of meltdown, triggering fears of default by its national oil company PDVSA, which has to make almost $5 billion in bond payments this year. urn:newsml:reuters.com:*:nL2N18A299

Venezuela's oil production has already fallen by at least 188,000 bpd this year.

In the United States, crude production C-OUT-T-EIA has fallen to 8.8 million bpd, 8.4 percent below 2015 peaks as the sector suffers a wave of bankruptcies. urn:newsml:reuters.com:*:nL2N18A18C

And in China, output fell 5.6 percent to 4.04 million bpd in April, year-on-year. urn:newsml:reuters.com:*:nL3N1891XA

Countering this, supply rose from the Organization of the Petroleum Exporting Countries (OPEC) as its producers are engaged in a race for market share. urn:newsml:reuters.com:*:nL3N1881CK

OPEC pumped 32.44 million bpd in April, up 188,000 bpd from March, the highest since at least 2008. urn:newsml:reuters.com:*:nL5N18A3BD

Also preventing steeper price jumps was a recovery in output in Canada following closures due to a wildfire, as well as bloated global crude storages. urn:newsml:reuters.com:*:nL3N18A3HL urn:newsml:reuters.com:*:nL2N18A0F5

"The inventory buffer may be preventing full price recovery and ... the market is rightly nervous about the sustainability of outages," said Morgan Stanley.

Barclays said that "while the supply-side disruptions are supporting oil market balances, refinery margins are starting to weaken, especially in Asia," adding that weaker demand from those refiners could produce "downside risk to prices in Q3 16." urn:newsml:reuters.com:*:nL3N18A3HL

(Reporting by Henning Gloystein; Editing by Joseph Radford and Richard Pullin) ((henning.gloystein@thomsonreuters.com)(+65 6870 3263)(Reuters Messaging:henning.gloystein.thomsonreuters.com@reuters.net))

Keywords: GLOBAL OIL/