The heads of some of the world's biggest oil companies countered on Monday OPEC claims that speculators were driving high oil prices, instead blaming a dearth of new supplies.

The record run-up in oil prices over recent years is igniting fierce debate over the "peak oil" theory — that once the maximum rate of global production is reached, a steep decline ensues.   Here we present two squarely opposed viewpoints on the issues from rivals who have been sparring for years. 

With growing talk about peak oil — when the globe’s petroleum reserves begin an inexorable decline — exploration companies are increasingly turning high-tech to delay this eventuality.   There's been stunning advances in the industry's ability to visualize what lies deep underground and to extract more of what's down there.

The future of this renewable energy source is bright,  especially since it's expected to be  cost-competitive within five years. And the US is well-positioned to benefit.

With the proliferation of energy-oriented mutual funds over the last ten years, getting a piece of this supercharged, if highly volatile, sector has never been easier. But energy funds have been notoriously hot and cold over the years, so investors should allocate no more than 5 percent of their total portfolio to this sector.

The seemingly endless surge in energy prices is lightening wallets at gas stations, but it's also a potential bonanza for investors.

Energy prices have been absolutely sizzling hot, more than doubling the last 12 months. And with heavyweights like Goldman Sachs predicting that prices will hit $150 a barrel by this summer, everyone -- from producers to governments to motorists -- has been obsessed with where oil prices are going.

Talks between British oil company BP and its Russian partners over the future of their lucrative joint venture TNK-BP have broke down after BP rejected a Russian ultimatum, sources close to BP said on Wednesday.

World oil production fell by 0.2 percent in 2007, the first decline since 2002, and proven oil reserves were flat, BP said in an annual review released on Wednesday.

The chairman of British oil major BP rejected as "apocalyptic" a prediction by the head of Russian gas giant Gazprom of oil prices soaring to $250 a barrel by the end of next year.

U.S. light, sweet crude futures rebounded from two days of sharp losses, ending more than 4 percent higher as the dollar weakened against the euro, prompting funds to switch assets to the oil markets.

A bout of risk aversion dented European stocks on Tuesday as jitters grew over potential credit-related problems at banks and inflation, while typically defensive stocks such as pharmaceuticals and food rallied.

This much is clear: European nation states are focusing on different ways of securing energy supplies for the long-term through a mix of politics and innovation.

Petrobras, the Brazilian oil producer that’s rapidly emerging as one of the world’s top companies, is “finding very good results” at its newly discovered off-shore deposits, Chief Executive Jose Sergio Gabrielli de Azevedo told CNBC in an exclusive interview.

British oil major BP beat forecasts on Tuesday with a 48 percent leap in first-quarter replacement cost (RC) net income, helped by record oil prices and strong profits from punting energy markets.