LONDON, Aug 31 (Reuters) - The restart of Libya's largest refinery on Friday will help tighten availabilities of Mediterranean sweet grades, while spot differentials on Russia's main export grade Urals drifted sideways with limited activity.

No bids or offers surfaced in the Platts window.

Libya's 220,000 barrel per day Ras Lanuf refinery, closed by the conflict which ended the rule of Muammar Gaddafi last year, restarted on Friday after a lengthy delay.

The refinery has been ready to resume operations since the end of last year but the restart was delayed due to disputes between Libya's state oil company NOC and refinery owner UAE-Lerco over payments for crude oil, industry sources said.

ID:nL6E8JV4RK

Libyan exports are expected to fall in October as the refinery runs domestically produced Sarir and Messla crude grades, said traders. Loading dates for Libyan cargoes are due to be announced on Oct. 10.

"There are fewer Libyan barrels in the market," said one buyer.

Algeria's state oil company Sonatrach has started offering October loading cargoes. Offers were around dated Brent minus 60 to 70 cents, said one trader.

"Sonatrach is the seller as usual but not aggressive so far," said one trader, who did not hear of any specific deals.

Equity sellers are not expected to receive their October loading dates for another week or so.

In tender news, Rosneft is expected to announce the results of its major tender for Urals cargoes loading over 6 months by Sept. 6 at the latest, one participant said. The Russian producer was said to have asked traders for higher bids, though traders pointed out this was quite common.

Saudi Aramco is expected to issue its October official selling prices next week, followed soon afer Iraq's state marketer Somo new prices.

Re-selling of Iraqi medium sour Kirkuk has been difficult, said one trader, as loading delays are still nearly a month long.

Iranian oil shipments have risen slightly in August from their lowest level in more than two decades, a Reuters survey showed. ID:nL6E8JUCR4 ID:nL4E8JM3BW

Until recently, Asian customers have had trouble circumventing the shipping insurance ban but more Iranian crude has been heading to Asia in August.

Japan has managed to overcome limitations with government-backed shipping insurance has encouraged purchases, sources in the survey said. A further increase in September is expected.

Japan's imports of Iranian crude oil fell to zero in July for the first time since 1981, trade ministry data showed. To compensate, Japan increased imports from the United Arab Emirates and Iraq, among other suppliers. ID:nL4E8JV1ZG

(Reporting by Julia Payne; editing by Keiron Henderson)

((julia.payne@thomsonreuters.com)(+44 0207 542 1836)(Reuters Messaging: julia.payne.reuters.com@reuters.net))

 ((For a database of oil supply and demand fundamentals upstream and downstream, Reuters subscribers can click on 
  http://bond.views.session.rservices.com/ce/
   ((MED CRUDE OIL DIFFERENTIAL AND OUTRIGHT PRICE ASSESSMENTS:                       
  0#BFO-DIF
       
  0#C-E
         Urals Med       
  BFO-URL-E
       
  URL-E
         Urals NWE       
  BFO-URL-NWE
     
  URL-NWE-E
         Kirkuk          
  BFO-KIR
         
  KIR-E
          Siberian Light  
  BFO-SIB
         
  SIB-E
         Saharan Blend   
  BFO-SAH
         
  SAH-E
         CPC Blend       
  BFO-CPC
         
  CPC-E
         Azeri           
  BFO-AZR
         
  AZR-E
      CRUDE ARBITRAGE STORIES  
  O/CRUDEARB
        CRUDE OIL TRADES   
  CRU/T
      NORTH SEA CRUDE REPORT  
  CRU/E
      AFRICAN CRUDE REPORT  
  CRU/WAF
             Russia oil export schedule, monthly             
  O/RUS4
      Russia oil exports, table, monthly              
  O/RUS3
      Russia oil output by company, monthly           
  O/RUS2
      Russia oil output/exports, monthly              
  O/RUS1
      Russia product export, monthly                  
  O/RUS5
       
  ENERGY
   energy speed guide        
  CRUDE/1
   crude speed guide    NYMEX crude  
  0#CL:
    ICE crude  
  0#LCO:
                
  OPEC
   OPEC                 
  NSEA
    North Sea     
  CRU
    crude oil            
  PROD
    oil products     
  DRV
    derivatives          
  PRO/E
   European products     
  O/L
    Latest ICE           
  O/N
     Latest NYMEX     
  OILOIL
     
  NYMOIL
    
  IPEOIL
    
  OILSPD
    
  OILARB
           
  CRDWLD
   
  PRODEUR
     
  PRODUS
    
  APROD
  )) ))

Keywords: MARKETS MEDITERRANEAN/CRUDE