LONDON, Oct 4 (Reuters) - The oil market is not focusing on the fact that global spare capacity to raise oil production is very low, Saudi Aramco's Chief Executive said on Tuesday, with Shell's Chief Executive saying investments will not shift because prices are high.

"(The market is) focusing on what will happen to demand if recession happens in different parts of the world, they are not focusing on supply fundamentals," Aramco Chief Executive Amin Nasser said at the Energy Intelligence Forum in London.

Putting spare capacity at 1.5% of global demand, he added that providing a buffer of spare capacity, which will be used up the moment China's economy opens up from coronavirus restrictions, was not just the responsibility of Saudi Aramco.

Speaking at the same event, Shell Chief Executive Ben van Beurden said current high prices do not easily translate into a shift in capital allocation given it can take decades for oil and gas projects to produce and start paying off.

"You cannot have a quick response to the market signals we are seeing today," van Beurden said, adding that Shell's overall strategy remained to pivot away from oil and gas products.

"We cannot live in this world without spare capacity."

If he had a spare $1 billion to spend, he would invest in the "energy system of the future", said van Beurden, who will leave Shell next year. (Reporting by Shadia Nasralla and Ron Bousso; editing by Jason Neely and David Evans)