West Texas Intermediate futures for August delivery dropped to $54.74 (-3.85%); Brent crude declined to $59.53 (-1.31%) a barrel amid the results of Greek referendum and more attempts to support China stock markets. Official figures have shown that 61.31% of Greeks rejected Europe's latest bailout offer and fueled fears of Greece's exit from the single currency area. Prospects of additional supply from Iran have also weighed on oil prices (various sources suggest that an agreement between Iran and global powers might be reached within days, allowing OPEC's fifth-largest producer to nearly double its exports).