McLaren CEO Ron Dennis says Formula One's regulations are delaying his team's return to competitiveness with new engine supplier Honda.

The revival of the McLaren-Honda partnership has not gone to plan so far, with the team scoring just 17 points this season as it has struggled with reliability issues and an uncompetitive power unit. In order to control costs, the FIA only allows power unit upgrades within the constraints of its token system as well as limiting in-season testing, wind tunnel time and CFD development at factories.

However, Dennis says the regulations have actually increased costs for engine developers, while limits on aerodynamic improvements only serve to create barriers for teams trying to close the gap to the front.

"I think the frustrations I have with the regulations is that everything that has been designed to reduce costs has increased it and primarily because the cost of getting durability is endless evaluation on dynos and test cells," he said. "I would like to go testing, I would like to have freedom in wind tunnels, freedom in CFD. When you are uncompetitive you have to develop your way out of it and at the moment the regulations are extremely constraining in that area."

Dennis says Honda is working hard to develop as quickly as possible, but will only spend tokens when potential upgrades prove themselves as significant performance improvements on the dyno.

"The misconception that many people have is that every time you change the engine you give up a token, but that is not the way it is. You develop the engine as much as you want, you have token freedom away from the circuit and the number of engines used, and it's only and when you have got significant improvements that you issue an engine change with the tokens.

"Theoretically in an ideal world that would be every fourth race, but we have tried to move forward faster and that has affected reliability and made the whole thing more challenging. In the end the very acute pain we have inflicted on ourselves is the fastest way to get back to where we need to get to."

Honda motorsport boss Yasuhisa Arai admits performance gains will be hard to come by for the remainder of the season, but has confirmed his engineers will change the power unit's layout for 2016.

"Already we know that we are behind and we have already started to prepare next season's engine, including some layout change, which I can confirm is on schedule."