The International Energy Agency has released its annual five year forecast for the energy industry. And it could deliver some bad news for OPEC. The IEA predicts a boom in US shale. And as Jacob Greaves reports from Dubai, that poses big issues for the oil cartel.

The second wave of US shale oil is coming. That's the message from the International Energy Agency's latest five year forecast. It thinks America will account for 70% of global capacity growth over that period. If true, that level would surpass Russian exports and bring it close to Saudi Arabia's crown as top exporter. Raising the question of OPEC's market share and whether in the future it can afford to cut supply to influence price.

SEAN EVERS, MANAGING PARTNER GULF INTELLIGENCE "At this moment in time there's certainly a need for both shale and everybody else's oil barrels, whether there will be a need in 5 years' time, the fight gets tighter, if peak demand happens. That's a big question, I suspect it will and I suspect OPEC will not be able to hold onto the maximized price over market share strategy they have done for the last fifty years."

It comes at a time when OPEC alongside the likes of Russia has been pursuing production cuts to try and boost oil prices, But as the US eyes a more influential future on export markets, questions are being asked of OPEC's room for growth.

JACOB GREAVES CORRESPONDENT "One of the main forecasts from the IEA is that many OPEC producers will struggle to make significant capacity increases over the next five years, with the agency claiming just Iraq and the UAE will be able to substantially boost resources."

Part of the issue might be courting investment.

HERMAN WANG, SENIOR OIL WRITER S&P GLOBAL PLATTS "OPEC faces a lot of challenges in trying to maintain its oil production. A lot of countries are faced with declining mature fields, they have to invest a lot of money to get those fields, to replace those barrels that they're losing to natural decline. And one of the messages OPEC has for the market is that they need to see more sustained investment in the industry. We're seeing a lot of investment in the US in this shale oil, the short cycle shale oil that brings about returns more quickly than the typical long cycle projects that take a lot of investment and sometimes take up to a decade even longer sometimes to payback what you've originally invested."

US sanctions on OPEC members Iran and Venezuela could further impact future capacity. For now the message from OPEC on US shale is that there's enough space for everyone. But that could change further down the pipeline, if it leaks market influence to what was once its biggest consumer. JG CGTN, Dubai.