BP Plc's stricken oil well showed no sign of leaking on Friday after a new cap stopped crude from flowing into the Gulf of Mexico, but US President Barack Obama cautioned there was more work to do before the gusher was permanently stopped. Spill
BP was conducting a pressure test after it choked off the well on Thursday. Underwater robots scanned the sea floor for signs of oil leaks, which could happen if the undersea well is damaged. A Look Back
"We've seen no negative evidence of any breaching there," said Kent Wells, BP's senior vice president of exploration and production.
Obama, speaking at the White House, cautiously welcomed the news. He said the halt to the oil flow was "good news," but cautioned it was not a final solution to the leak which has triggered the nation's worst ever environmental disaster.
A permanent end to the spill is not expected before mid-August, when two relief wells should enable BP to fill the ruptured wellbore with cement, drowning the oil flowing up from a huge undersea reservoir.
The tests are due to finish on Saturday, when crews plan to resume capturing and siphoning away the oil while the results are examined.
But Gulf residents now hope new attention will be given to the clean-up operation, with the shorelines of five states ravaged, Gulf fishing waters closed and tourists shunning the usually popular beaches.
Obama acknowledged there was still "an enormous amount of work to do," but called on Americans to remain positive.
BP's shares up
BP's shares rose in London on Friday on hopes that it has at last been able to stop the oil that has been leaking into the Gulf of Mexico for the past three months and can focus on the cleanup.
It was the first time BP managed to cap the flow since the April 20 explosion that killed 11 men and caused the worst offshore oil spill in US history.