Russian Urals crude weakened in the Mediterranean on Monday and paper swaps showed potential for the grade to lose further ground in August.
In the Platts window, Litasco offered an 80,000 tonne cargo in the Mediterranean at dated Brent minus 65 cents, some 20 cents weaker than previous price estimates, but found no buyers, traders said.
Urals August swaps showed prices could weaken to dated Brent minus 60 to 75 cents in the Mediterranean and by some 10-15 cents in the Baltic from the current levels of dated Brent minus $1.20-1.30 a barrel.
"It looks like August could be similar or slightly shorter than July in terms of volumes. So prices will most likely remain range-bound," said a trader with an oil major.
He said uncertainty remained over whether Russia would perform a several day maintenance at the port of Primorsk in the Baltic in addition to a maintenance in the first 10 days in the neighbouring Baltic port of Ust Luga.
The final Russian loading schedules are due at the end of this week.
Libyan war planes sank one ship and attacked a second vessel on Sunday near the eastern city of Benghazi, military spokesmen for the country's internationally recognized government said on Monday.
Saudi Arabia's crude oil exports fell to their lowest in five months in May despite near record production, as the OPEC kingpin turns itself into a major refined-fuels power and as domestic consumption rises.
(Reporting by Dmitry Zhdannikov; Editing by David Holmes)