Browne is due to retire soon. I think he's just being mischeivous.

Obviously a lot of people don't have their own opinions on this and will listen to people am eminent as Lord Browne - I mean he must know what he's on about.  The question we should be considering is why he is saying that?  Why does he want people to believe those figures?

Remember Total's head of exploration Christophe de Margerie, telling The Times in April that "120 million barrels per day will never be reached, never" adding "The world lacks the means to produce enough oil to meet rising projections of demand for fuel over the next decade." (TOD Link)

''Oil supply to peak sooner than we think, says BP scientist
Richard Orange
November 07, 2004 6:00 AM (GMT)

WORLD oil production is likely to peak in the next decade, much earlier than many international forecasts, a senior BP executive has told The Business.
BP exploration consultant Francis Harper said he estimated the world's total original usable oil resources - the amount of oil before drilling began - at about 2.4 trillion barrels of oil. This is considerably less than the 3 trillion assumed by bullish commentators such as the US government's Geological Survey. This points to oil production peaking between 2010 and 2020.
His comments are a rare entry by a global oil company into the debate on the life of global oil supplies. If true, it would mean demand outstripping supply much earlier than energy projections by ExxonMobil and Shell. BP does not officially supply projections.
The International Energy Agency, the industry watchdog, expects oil demand to continue to rise until 2030. It assumes production will rise to meet demand.
Harper will argue at a London conference this week that production would start to slow in non-Opec members, concentrating the cartel's power.
He said: "When the world peaks isn't the critical thing. What's more salient is when non-Opec oil peaks, then you'll have the control of marginal production passed back to a progressively smaller group of countries."
He added that oil companies' public positions on the issue masked debate within them. "There are people in BP who happen to be economists and so happen to think there's no problem, and there are people in BP who are geologists who are saying it's getting hard to find."
Harper's prediction is higher than the 2 trillion posited by doom-sayers like Colin Campbell. Harper said: "I'm more conservative than Exxon Mobil with regard to future oil resources, but I'm not Colin Campbell."
Seth Kleinman at PFC Energy said oil companies had held back from such statements. "There's a certain degree of hesitancy for oil companies to go on the record and say, 'we are doing well with oil prices where they are now, but 10 years down the road things actually look pretty dire'."

Repeated from within the text above:

"There are people in BP who happen to be economists and so happen to think there's no problem, and there are people in BP who are geologists who are saying it's getting hard to find."

Instead of following the words of CEO's I prefer to 'follow the money'.  BP plan to return $65bn to shareholders in form of stock buybacks and dividends over the next 3 years; this money is thus denied for funding exploration and new field development.  More specifically regarding one of the 'giant' fields in Caspian region here's what BP (and BG and Statoil) actually did:

In the early nineties the Caspian seemed to be the next Middle East. In 2001 we had 20 out of 25 dry holes that dampened the enthusiasm for the Caspian significantly. In 2001 Kashagan was finally discovered, deemed to be the greatest field in the decade. In 2002 BP and Stat Oil quietly sold their 14% of Kashagan for 800 million dollars. In 2003 British Gas put their 17% on the block for 1.2 billion dollars. Which raises, in my opinion, the question, "What do these original parties know about the world's greatest field or do they merely want to spread the wealth?

Some of the background behind BP's decision to exit is discussed here: Caspian Oil Myth

If Caspian region really does hold the 200 Gbbls that Browne refers to why did BP reduce its presence in the area?