* Plant may have been intended for uranium conversion-paper
* Report may increase pressure for IAEA action
* Like Iran, Syria has denied nuclear weapons aims
(Adds Israeli comment, analyst, details)
VIENNA, Feb 24 (Reuters) - Western intelligence agencies suspect Syria may have been building a secret nuclear-related site near Damascus, a German daily said, and a U.S. think-tank suggested it could be linked to a site bombed by Israel in 2007.
If confirmed, Thursday's report by the Sueddeutsche Zeitung newspaper would add to Western fears that the Arab state had engaged in covert nuclear activity before the Israeli attack and may increase pressure for action by the U.N. nuclear watchdog.
Israeli Defence Minister Ehud Barak said in Jerusalem:
"The international authorities as well as intelligence organisations know this information, and the International Atomic Energy Agency is working to gain access to inspect this place, and this is the right thing."
The Institute for Science and International Security (ISIS), a Washington-based think-tank, said the operational status of what it suspected was a small uranium conversion facility near the town of Marj as Sultan was not known.
"However, there is suspicion that Syria may have emptied the buildings prior to mid-2008 and taken steps to disguise previous activities at the site," it said in an analysis issued alongside the German newspaper report.
For more than two years Syria has refused to allow U.N. inspectors to revisit a site destroyed by Israel in September 2007, which U.S. intelligence reports said was a nascent North Korean-designed nuclear reactor intended to produce bomb fuel.
Sueddeutsche Zeitung said it had obtained photographs supposed to have been taken from inside two buildings at another location, near Marj as Sultan, about 15 km (9 miles) east of the capital and bordering a military site.
It was not known exactly when they were taken, it said, adding the equipment was partially installed at the time.
"But together with other information they allow for the first time the credible suspicion that Syria was in the process of setting up a facility for so-called uranium conversion -- a preliminary stage for producing fuel rods which could be used in the suspected reactor," it said.
The paper said it had decided not to publish the photographs in order to protect its sources.
ISIS said the Marj as Sultan complex may have been functionally linked to the Dair Alzour facility, also known as al-Kibar, attacked by Israel more than three years ago.
There is a "strong suspicion that was a uranium conversion facility related to the process of making fuel for the al-Kibar reactor," ISIS research analyst Paul Brannan told Reuters.
Syria, an ally of Iran, denies ever harbouring an atom bomb programme and says the IAEA should focus on Israel instead because of its undeclared nuclear arsenal.
There was no immediate comment on Thursday from Syria's mission to the U.N. atomic body, the Vienna-based IAEA.
Syria has repeatedly rebuffed requests by the IAEA for follow-up access to Dair Alzour and three sites related to it, saying they are non-nuclear, military installations.
ISIS said satellite images from July 25, 2008, showed considerable activity at the Marj as Sultan facility, which it believes is one of the three additional sites.
"What I see as most significant is the actions that Syria takes to throw a roadblock in the way of the IAEA. It knew that the IAEA was going to want to visit these sites," Brannan said.
The IAEA is due to issue its quarterly reports about Iran and Syria ahead of a March 7-11 meeting of the Vienna-based body's 35-nation governing board.
The United States has suggested that the IAEA may need to consider invoking its "special inspection" mechanism to give it authority to look anywhere necessary in Syria at short notice.
Some diplomats in Vienna have cautioned against any such move, saying it would distract attention from the more pressing issue of Iran, which Western powers suspect is trying to develop nuclear weapons capability. Tehran denies this. (Reporting by Fredrik Dahl and Michael Shields in Vienna and Dan Williams in Jerusalem; Editing by Jon Hemming)