Anglo-French oil company Perenco's UK unit said on Sunday that a limited oil leak occurred at one of its well sites in Wytch Farm in Dorset, southern England.
Perenco UK said the spill was being contained and an investigation will be launched.
"Any spill is an extremely serious matter and a full investigation will be launched to ascertain what happened in Poole Harbour," Perenco UK's Wytch Farm General Manager Franck Dy said in a statement.