Toyota Formula One boss Tsutomu Tomita will stand down at the end of June and be replaced by Tadashi Yamashina, the team said on Thursday.

Yamashina has been Toyota Motorsport vice-chairman since December last year.

Toyota said in a statement that Tomita, 63, would be re-assigned to a new role in Japan within the car manufacturer's group of companies.

"I am looking forward to celebrating Toyota's first victory in Formula One, which I believe will happen sooner rather than later," said Tomita, who publicly apologised earlier this year for the Cologne-based team's failure to win in 2006.

Toyota are estimated to have spent well over $1 billion on Formula One since their debut in 2002 but their achievements till now are meagre: two pole positions, one fastest lap and two second places for Italian Jarno Trulli in 2005.

The team are currently fifth in the constructors' championship with five points from three races.