North Sea Crude-Differentials slip as French refineries stay offline

LONDON, May 31 (Reuters) - * North Sea differentials edged lower on Tuesday to touch a fresh four-week low as strikes at French refineries continued and an overhang of unused crude lingered in the region.

* Workers at oil storage and supply services company CIM, which handles about 40 percent of French crude imports, voted on Monday to extend their strike at Le Havre port until 1000 GMT on Wednesday, a CGT union official told Reuters.

* Only two French refineries out of eight are operating, but the situation at depots has improved from last week with only one now blocked.

* Supply of Oseberg crude is expected to fall in July to six cargoes from the seven scheduled to load in June, trade sources said on Tuesday. The six cargoes listed in the programme will load 3.6 million barrels of oil, at a daily rate of around 116,000 barrels per day, the schedule showed.

* This compares with a daily loading rate of 140,000 bpd in the June programme.

* The rest of the BFOE loading programmes for July are due to be released on Wednesday.

* Reuters shipping data shows Shell (LSE: RDSB.L - news) has chartered at least three VLCCs to load Forties this month, which, if all three make the trip, will mean the company will have exported more Forties to Asia than any other so far this year.

WINDOW SUMMARY

* Petroineos bid for a cargo of Forties for loading June 18-22 at a premium of 4 cents to dated Brent.

* Unipec offered a cargo of Forties for loading June 12-14 at 35 cents above the price of dated Brent.

* This compares with the last assessment on Friday for Forties at 5 cents above dated Brent.

* Vitol offered a cargo of Brent at a discount of 30 cents to dated Brent for loading June 12-14. Brent was the lowest-priced crude and therefore sets the level of the dated benchmark.

* Unipec withdrew a bid of a cargo of Oseberg for loading June 14-16 at a premium of 95 cents to dated Brent. After applying the quality premium for June-loading cargoes, this equates to a bid of 4 cents above the price of dated Brent. (Reporting by Amanda Cooper; Editing by Susan Fenton)