Brent crude oil's premium to Dubai crude fell to the lowest in more than two months after the international benchmark weakened on the prospect of Russia and OPEC adding more supplies, Reuters data showed on Friday. The prompt July Brent-Dubai EFS was at $3.45/bbl at Friday's close in Singapore, down 15 cents from the previous session, the data showed. The narrower spread will encourage Asian refiners to buy more Brent-linked grades from the Atlantic Basin and reduce spot premiums for Middle East and Russian grades priced against Dubai.