UPDATE 1-Brent steady near $108 ahead of Iran nuclear talks
* Iran agrees to talks with six world powers, including U.S.
* Iraq boosts oil output after stopping pipeline leak
* Libya may reopen eastern Hariga port this week -official
* Coming up: U.S. consumer confidence; 1400 GMT
SINGAPORE, Sept 24 (Reuters) - Brent crude held steady near $108 a barrel on Tuesday as geopolitical tensions eased slightly ahead of nuclear talks involving Iran and the United States later this week, while rising oil supply from Iraq and Libya weighed on prices.
Iran has agreed to new talks on its nuclear programme with top diplomats from six world powers, including U.S. Secretary of State John Kerry, raising hopes that Tehran's relations with the United States could thaw.
U.S. officials have also said a meeting is possible this week between President Barack Obama and Iran's new centrist president, Hassan Rouhani.
"Geopolitical tensions are reducing and oil output is rising so these two factors are driving oil futures to moderate," IHS analyst Victor Shum said.
Brent crude for November delivery edged down 7 cents to $108.09 per barrel by 0637 GMT, after settling at its lowest close in four sessions on Monday.
November U.S. crude was off 8 cents at $103.51 a barrel, down for a fourth day after touching a six-week low in the previous session.
Investors are closely watching for any signs of easing tensions between Iran and the United States. Sanctions from the West aimed at ending Tehran's nuclear programme have sharply reduced Iranian oil exports over the past two years.
"The geopolitical tone over Iran has been dialled down. The other development is the continuing progress over Syria's situation," Shum said, adding that these developments have reduced geopolitical premiums in oil prices.
The United Nations may back a U.S.-Russian plan to rid Syria of chemical arms this week.
Syria is not a major oil producer but traders always worry that any escalation of violence in the Middle East could disrupt oil flows.
Oil supply has, meanwhile, improved as Iraq boosted output from its Rumaila field after plugging a leaking pipeline, although planned work continued to keep a lid on exports from OPEC's No. 2 producer after Saudi Arabia.
Libya is also gradually ramping up output after protests crippled its oil sector. The OPEC producer could reopen its eastern Hariga port this week but there was no progress opening larger eastern terminals that have been shut for weeks, a senior government official said on Monday.
In global financial markets, the uncertainty about when the U.S. Federal Reserve will start trimming its massive stimulus programme kept investors on the edge.
(Editing by Tom Hogue)