"Oh yes, for the long-term future definitely and for various reasons," the German, younger brother of Ferrari's seven times champion Michael, told reporters at the launch of the Germany-based team's 2005 car in Barcelona.
"There are a lot of capable people at Williams but it's still a very small company," he added.
"And it all depends on two people basically -- on Frank (Williams) and Patrick (Head) and they are not the youngest any more and they don't have a manufacturer behind them as well financially.
"These days a lot of Formula One is about having finance power and I think Toyota is a far better option."
Ralf will make his Toyota debut at the season-opening Australian Grand Prix on March 6 after six years with BMW-powered Williams in which he won six races.
"I tried it for six years and eventually for whatever reason it never worked out so I think it was time to move on," said the 29-year-old.
Toyota, in three seasons in Formula One, have yet to secure a podium finish and must now raise their game.
LONG-TERM
Ralf's manager Willi Weber is keen for Toyota to build around him in the same way that Ferrari have focused on Michael. But the driver, while hinting that it might be a future strategy, played down such talk.
"I think it simply depends on who is quickest," said Ralf. "If Jarno (Trulli) is the quicker driver then it will happen around him but first of all I think that's not the priority really from where we are.
"For the moment it needs the two of us to work closely with the team to get results or to get the car where it should be."
Ralf, reunited with technical director Mike Gascoyne after working together at Jordan in 1998, saw his move as a 'long-term project'.
"I think beyond three or four years anyway," he said. "That's what it takes. You saw it with Michael (now starting his 10th season with Ferrari), you saw it with other teams.
"Especially in Formula One a season goes by so fast, it's amazing. The year is over and you haven't even realised.
"My main target is to be world champion and now I have a perfect opportunity with a young team with all the possibilities regarding this team.
"They have a different way of approaching drivers and people here which I only see as a good way. Williams just had a different way."
Ralf said he had been "desperately looking' for a team, like Ferrari, that made everything under the same roof but he had not discussed his move with his sibling before making his mind up.
"When I told him that I was going to take that decision he said it was very ambitious but the right decision for the long-term, it's just a question of how long it takes.
"For me it was the perfect choice. It was a difficult decision to leave a team which you have been in for six years. I got along with Williams a lot better than it seemed to be sometimes.
"I had my fights with Frank and Patrick but that's normal, they are strong characters."
