(Adds comments from BP press relations officer, details on tests, and background) NEW ORLEANS (AFP)--Energy giant BP said Saturday it will continue pressure tests on the Gulf of Mexico oil well beyond the initial 48 hour period as it remains capped, a company spokesman told AFP. "We're moving forward six hours at a time. If there's a change in what we're doing we will announce it," said BP (BP, BP.LN) press relations officer Mark Salt, declining to elaborate on pressure readings or where the test is heading. BP's test continues as a "conditions-based process," said Salt, with consultations between BP and government engineers on whether to keep going after each six-hour marker. The tests will determine whether the cap can remain sealed over the leak or BP will have to return to a containment system of siphoning off gushing crude to production vessels waiting on the sea surface. Earlier Saturday, BP senior vice president Kent Wells said the "longer the test goes, the more confidence we have in it." The test ended its initial two-day limit at 1 p.m. (1800 GMT). The critical tests are assessing the integrity of the wellbore, which runs deep into the sea floor into the oil reservoir below, and identifying the pressure created by sealing the leak from above. The pressure readings have so far been positive, but not conclusive. Engineers had hoped to register readings of up to 8,000-9,000 pounds per square inch (psi), a high reading that would mean the well is still intact and there is no seepage. But the most recent reading Saturday had the pressure at around 6,745 psi, with Wells warning: "We could have integrity or we could not have integrity between the 6,000 or 7,500 psi." (END) Dow Jones Newswires July 17, 2010 16:41 ET (20:41 GMT)