BP cap tests suggest possible leak

Pressure readings from a new containment cap that stopped theflow of oil from BP's broken wellhead indicate there could be a leak down in the well, the U.S.government's point man on the disaster says.

Developments were "generally good news"butclose monitoring mustcontinue, retired coast guard admiralThad Allen said on a conference call.

Engineers continue to look for evidence ofleaks as pressure readings from the cap are examined, Allen said.

He said scientists believe the pressure levels could indicatethat the reservoir the source of the oil is depleting after a three-month spill or that there's aleak somewhere down in the well.

"We don't know because we don't know the exact condition of the well bore," Allen said.

BP closed the choke valve on the new cap over its damaged wellhead off the Louisiana coast Thursday afternoon stemming the flow of oil into the Gulf for the first time since the well blew outApril 20 in an oil rig explosion.

Allensaid the test will go ahead for another six-hour period before being reassessed to see if BP needs to reopen the cap and go back to piping some of the oil to ships on the surface.

The testingis to take place over48 hours. Any new leaks would mean the cap would have to be reopened and oilwould againbe allowed to spill into the water.

If the testing proceeds as expected, it should wrap up Saturday afternoon.

Earlier, U.S. President Barack Obama said BP is making progress in stopping the flow of oil into the Gulf of Mexico, but a permanent solution is still needed.

Obama said Friday that scientists are monitoring thecap teststo ensure "we are taking a prudent course of action" and not simply looking for a short-term solution that could "lead to even greater problems down the road."

He said the placement of the new capis "good news,"noting thatthe new system will be used to stop the flow of oil or to capturemuch ofthe gushing oil until a relief well,whichis seen asthe more permanent solution to stopping the flow of oil,is finished.

"We're not going to know for certain which approach makes sense until additional data is in," he said, assuring the public that all decisions will be based on science and what is best for Gulf area residents.

Obama added that even if the cap can't completely shut off the flow of oil, it will allow BP to attach "many more containment mechanisms" so more oil can be channelled to ships on the surface instead of flowing into the Gulf.

Relief well essential

Kent Wells, a BP vice-president, saidpressure is good inside the new cap and there were no signs of new leaks. He also said work would resume on one of two relief wells BP aims to drill.

Obama stressed the importance of the relief wells, saying: "We won't be done until we know that we've actually killed the well and have a permanent solution in place."

Though the flow of oil has been temporarily halted, Obama cautioned that it will be an enormous task to clean up the hundreds of millions of litres that have already poured out of the blown-out well.