Viral media created an immense burden on BP's communications team during the Deepwater Horizon crisis, former BP CEO Tony Hayward told a gathering of the U.K. agency Loewy Group this week.

Hayward called the media environment "vicious" during the spill and said his company was "at war with the media every day," according to a recap of the event by PR pro Steve Earl, who works at Lowey unit Speed Communications.

Hayward said in retrospect that he would have had more of his senior team around him to handle communication with the media and noted one of the main PR lessons for large corporations is that plans for crises must be made and tested regularly.

Read Earl's full recap here.

O'Dwyer's reported last week that U.K. agency Finsbury is guiding PR for Hayward's "comeback," a $1.6B public offering for his Vallares investment vehicle on the London Stock Exchange.