* Supply rises by 280,000 bpd led by Iraq, Iran, Libya
* Saudi output little changed as exports flatline
* OPEC pumps 460,000 bpd above target
By Alex Lawler
LONDON, April 30 OPEC crude oil output has rebounded in April from its lowest monthly level in more than a year due to the resolution of export disruptions in Iraq and Libya and a rise in Iranian sales, a Reuters survey found.
Supply from the Organization of the Petroleum Exporting Countries is set to average 30.46 million barrels per day (bpd), up from 30.18 million bpd in March, the survey of shipping data and sources at oil firms, OPEC and consultants found.
The survey indicates supply has risen due to fewer output disruptions rather than any strategy to pump more oil. Top OPEC exporter Saudi Arabia, which cut supply at the end of 2012, is keeping a lid on output, as are its Gulf Arab OPEC allies.
"It's to be expected," Paul Tossetti, senior energy adviser at PFC Energy, said of April's supply increase. "The Saudis cut production and were supported by others, but it was all involuntary."
Oil, trading near $104 a barrel, has fallen from almost $120 in February on concerns about the global economic outlook, though it is still above Saudi Arabia's preferred level of $100.
OPEC's March output was the lowest since October 2011, when the group produced 29.81 million bpd, according to Reuters surveys. This month, OPEC is pumping 460,000 bpd more than its supply target of 30 million bpd, in place since January 2012.
According to the survey, Saudi Arabia has kept output steady at 9.25 million bpd this month. Domestic demand tends to rise in April due to a seasonally higher need for crude to fuel power plants, although industry sources say exports have been flat.
OPEC is scheduled to meet on May 31 in Vienna to review output policy for the second half of the year. At present, OPEC is expected to keep the target unchanged, leaving the door open for Saudi Arabia to tweak supply depending on demand.
Saudi Oil Minister Ali al-Naimi may give details on Saudi production and hints about output policy later on Tuesday, when he is due to give a speech in Washington.
Brent crude, which hit a 2013 high of $119.17 a barrel on Feb. 8, was trading just below $104 on Tuesday.
IRAQ EXPORTS RECOVER
Iraq, Libya and Iran have been the drivers of the rise in OPEC's output this month.
Iraq, the world's fastest-growing exporter, has shipped about 200,000 bpd more from its southern ports due to fewer weather-related disruptions. Exports of Kirkuk crude remain restrained by a dispute between the central government and the Kurdistan region over payments.
Output has risen in Libya, which resumed pumping oil to the port of Zueitina in early April after a blast halted flows. Also protesters ended a blockade of a field belonging to Conoco's Waha Oil, which industry sources said had affected output.
Iran's crude exports have edged higher in April to around 1.10 million bpd from a downwardly revised 1.03 million bpd in March, according to the survey.
In April, some Asian customers including South Korea have bought more Iranian crude due to the ending of maintenance at refineries, industry sources said. Taiwan, not a customer in recent months, is likely to have bought Iranian oil in April, industry sources said.
U.S. and European sanctions led to a sharp drop in Iranian exports last year. Iranian shipments are down from a post-sanctions high of at least 1.4 million bpd in December.
Supply in Nigeria, disrupted in the past few months by oil spills, flooding and theft, remains under downward pressure. Exports of Bonny Light crude are again under force majeure due to repair work on a pipeline. (Editing by Jane Baird)