1506 GMT [Dow Jones] Ambrian has lowered BHP Billiton's (BHP) rating to a hold from a buy and target price to 2,180p from 2,800p due to concerns that BP's (BP) oil spill may have negative consequences for all oil operators in the Gulf of Mexico. Also a cooling off in global economy during the summer months is likely to limit upside. "We think that sentiment on equity exposure to [BHP] is turning to the downside, given its exposure to the mess in the Gulf of Mexico and the concern over the potential financial fallout of BP's accident for the rest of the operators in the Gulf of Mexico," says Ambrian. The Gulf of Mexico accounts for a third of BHP Petroleum's oil profits. BHP Petroleum accounts for about 30% of BHP's Ebitda, Ambrian adds. BHP -0.1% at 1917p. (alex.macdonald@dowjones.com) Contact us in London. +44-20-7842-9464 Markettalk.eu@dowjones.com (END) Dow Jones Newswires June 16, 2010 11:06 ET (15:06 GMT)