RIYADH/LONDON, Oct 23 (Reuters) - The chief executive of French company TotalEnergies said on Saturday the recent gas price spike had been caused by a strong demand rebound post COVID-19 and prices were likely to stabilise after winter. "I don"t think it (gas price hike) is sustainable. Gas prices could come back after winter time," Patrick Pouyanne said, speaking at the Saudi Green Initiative Forum.Excluding oil and gas was not the right approach to energy transition, he said, arguing that a lack of investment in hydrocarbons could itself create a crisis. "Where is the right balance between the energy of the present and building the future? Yes, we need to invest more and more in decarbonised energy, but at the same time we need the people of this planet to receive reliable, affordable energy," he said. "If we don"t invest enough, we have crisis." Like its rivals, TotalEnergies has come under pressure from climate campaigners and some shareholders to speed up the shift from fossil fuels to cleaner sources of energy. It has argued that fossil fuels will continue to be needed during this transition period. The group wants to accelerate the growth of its investments in renewables and electricity, bringing them to $3 billion per year, or nearly 25% of its investments over the period 2021-2025. It aims to be one of the world"s top five renewable power producers, with 35 gigawatts of capacity by 2025, and 100 gigawatts by 2030, he added. Meanwhile it will continue to dedicate 75% of its investments to oil and gas, 50% to oil and 25% to increase gas production. "We continue to increase our capacity for gas," he said, adding that gas would remain an energy of transition.