A fusion reactor called Iter is currently under construction in France and is due to start operation in 2020. Its principal goal is to determine the viability of fusion at the scale of a power station. Success is widely anticipated and there are already plans afoot to build a "demonstration power plant" to start operating in the 2030s.
The construction phase of Iter is projected to cost €13bn ($17bn), a sum that is dwarfed by the annual subsidy to the fossil fuel industry, which the International Energy Agency estimated to be at least $400bn in 2010 alone. Moreover, the cost is shared between the seven Iter members (the European Union, China, India, Japan, South Korea, Russia and the US) and amounts to a UK contribution of a mere few tens of millions each year. The stakes are surely too high to quibble about funding at this level.