WASHINGTON: BP confirmed said Monday it had successfully placed a new cap over the Gulf of Mexico oil leak, hoping the giant valve will seal the well or contain all the gushing crude.

An integrity test lasting between six and 48 hours will begin on July 13 to properly assess the well, BP said, without indicating exactly when it would begin.

"It is expected, although cannot be assured, that no oil will be released to the ocean for the duration of the test," the oil giant said in a statement, adding however that it would not indicate if the flow had permanently stopped.

BDST: 0912 HRS, July 13, 2010