Chief executive Bob Dudley said the media was putting unrealistic demands on Mrs May by expecting her to reveal the finer details of Britain’s exit from the European Union on a daily basis.
Speaking to CNBC at the Egypt Petroleum Summit in Cairo, he said his experience of negotiating led him to believe that clarity over the Brexit agreement would be found closer to the deadline.
He said: “I mean I’m sympathetic to the Prime Minister for everyone wanting to know every move she’s going to make.
“In oil and gas you negotiate all the time constantly. You don’t do them publicly.
“And in my experience negotiators don’t come together until closer to a deadline. So, I think it’s unrealistic for her to negotiate in public. I think that’s not good for the country, actually.”
Mr Dudley also backed the oil giant to remain rooted in Britain after Brexit, saying BP was “deeply committed” to the country.
The comments after the oil major secured one of the strongest years in its recent history last week after a hike in the cost of crude helped annual profits more than double.
The energy giant saw underlying replacement cost profit - BP’s preferred income measure - soar to 6.2 billion US dollars (£4.4 billion) for 2017, up from 2.6 billion US dollars (£1.9 billion) the year before.
BP is among a string of oil majors benefiting from climbing prices, having seen Brent crude hit 70 dollars per barrel last month - its highest level in more than three years.
However, Mr Dudley said on Tuesday that he expected Brent crude to track below the 70 dollars a barrel mark in the coming years, with the group planning for prices of 50 dollars to 65 dollars a barrel by the end of the decade.