Reports from Barcelona on Tuesday said “huge” pressure had opened up between the two sides as Honda grapples with engine problems for the third consecutive year.
But McLaren boss Boullier said McLaren and Honda are sticking together.
“We have a contract,” he said. “A long term contract, and we want to build on it even if it is not ideal times.
“Seriously, we don’t think about these things. Even if there are difficulties, a separation is absolutely not an issue.”
And while he admitted that every McLaren-Honda fan is right to be “losing patience” with the situation, Boullier said the current problems are not as bad as 2015.
“It seems complicated to the outside world,” the Frenchman is quoted by Germany’s Auto Bild, “but internally, two problems are always the same.
“We know we can solve this problem. We must be able to rely on our partner, and we do.
“For Australia we will have a new engine and we hope that all the problems are solved. What I don’t know yet is if we can have it (the new engine) this week,” he is quoted by Spain’s El Pais.
Some reports, however, insist that separate to Honda’s problems, the new McLaren chassis is also not handling well around Barcelona.
“I read some articles and I think of Donald Trump and his ‘fake news’,” Boullier smiled.
“We have a good car, even though the McLaren here is not the McLaren you will see in Australia.
“But the forecasts at the moment are that we will probably have to change some engines in the first races,” he admitted.