TOKYO (Reuters) - Tokyo 2020 organisers vowed no let-up in their drive to host a successful Summer Games on Monday as International Olympic Committee (IOC) President Thomas Bach once again heaped praise on the city's preparations.

Bach, in opening remarks ahead of a meeting between IOC and 2020 officials, repeated that Tokyo was the most prepared city for an Olympics he could remember, and while organisers were happy with the compliments they said there was much work to be done.

"We have a saying in Japanese that says that loosening your tension is a big enemy," said Tokyo 2020 President Yoshiro Mori.

"So we shouldn't be too relaxed.

"We ... will work hard for the success of this big project and do hard work even in its small things because those are the most important things."

With some 600 days to go until the start of the Games on July 24, 2020, organisers find themselves in a relatively comfortable position, with preparations back on track following some initial bumps in the road.

In 2015, Tokyo 2020 scrapped their initial Games logo due to allegations of plagiarism and the original design for a new Olympic stadium was also changed due to costs.

However, since budget cuts of $300 million were announced in December last year, organisers have had a relatively pain-free ride.

Despite this, there is still work to be done, especially regarding transport, accommodation and counter-measures to the summer heat in Tokyo, which reached a record 41.1 degrees Celsius in July this year.

Bach said organisers had to guard against complacency as preparations enter the home stretch.

"I cannot give this Coordination Commission any major tasks here but only the warning," said Bach, who delivered a similar message following the IOC Executive Board meeting at the weekend.

"I know it is unnecessary, knowing the Japanese people, .... but we should never get complacent.

"I know I don’t need to say this to Japanese people and I know I don’t need to say this to my friends and colleagues in the Coordination Commission."

Bach said preparations for 2020 were well in advance of those of previous Olympic hosts

“In some of the (host) cities – even in most – we had to organise crisis meetings with the Executive Board a couple of months before the Games and some of them, maybe three months before the Games, were maybe not where you are today already,” said Bach.

"So, you have really reached a very high level of preparation."

The next landmark for organisers will be the announcement of the next version of the budget later this month.

(Writing by Jack Tarrant, Editing by Peter Rutherford)