Okada replaces Ivica Osim, who has been in hospital for the last month after suffering a stroke, and will coach the national team until the end of the 2010 World Cup.

It is the 51-year-old's second stint with the Japan national team after coaching them at the 1998 World Cup.

"As a coaching colleague and a football colleague, I really feel so sorry that Mr Osim cannot continue his job," said Okada at a news conference held at the JFA headquarters in Tokyo.

"I didn't even think I would be in this situation a week ago. I actually turned down an offer from a J.League club.

"But when I was offered this job I thought I should do something about this and after thinking it all through I agreed to do it.

"I will do all I can do to take Japan to the World Cup."

Okada will take charge of Japan for their first game in the World Cup qualifiers against Thailand on February 6.

The former Yokohama F. Marinos manager will name a squad for a one-day training match in the middle of this month to meet the players and tell them what to work on ahead of a 10-day training camp starting from January 15.

Asked about the qualifiers, Okada added: "I'd like to take it one game at a time. When we have four games in June, we will have more time to work together.

"But until then, I'd like to focus on the first two games, Thailand and Bahrain, and make our team ready for them with what we have available."

Osim, meanwhile, is showing signs of recovery from his stroke having verbally communicated with his family.

The JFA is ready to offer Osim a position if the Bosnia-born coach wants to get involved with Japanese football once he returns to full health.