The American held talks in the Japanese capital today with Tokyo Governor Yuriko Koike, who commissioned a report published last week which claimed the budget for the Games would balloon to ¥3 trillion (£22 billion/$30 billion/€26 billion) unless drastic changes are made.

These include moving the rowing and canoe venue to Tome in Miyagi Prefecture, 400 kilometres outside Tokyo. 

Haggerty admitted that major changes needed to be made to Ariake Tennis Forest Park, the proposed venue for Tokyo 2020, but he did not believe there was any danger of it being moved.

"We really didn't speak that long, so I don't know," he told Japanese news agency Kyodo News. 

"She didn't say, 'Dave, I agree 100 per cent and tennis will have everything.' 

"She didn't say that, but I think that she was certainly open-minded about things.

"She said that the tennis event, the venue, is very good. 

"We agree [on that]. 

"And we talked about the need to upgrade the facility to make it world-class for 2020 as we look out from now what the needs will be."

The venue, opened in 1987, is currently staging the Japan Open Tennis Championships but Haggerty claimed changes needed to be made before Tokyo 2020.

These include the construction of two new show courts - one with 5,000 seats, the other with 3,000 - and upgrading the stadium's retractable roof.

"In my brief conversation last night with the Governor, she did mention that they were stopping a few other venues because they felt that they have existing facilities in place where those sports could be played," Haggerty told Kyodo News.

"She did say in the case of tennis that you have a facility and the plan from the beginning was to use this facility and make it better."

Kris Dent, the ITF's executive director of professional tennis, admitted they were keen to finalise plans for Tokyo 2020 so they can avoid some of the plans that affected preparations for Rio 2016. 

"For us this week, we will be looking to get a better idea of construction timelines, particularly when they are due to finish," he told Kyodo News.

"I think we are looking at the moment between late 2017 through to the fall of 2019. 

"That is obviously key and that would then determine when the test event or test events are held late into 2019.

"That is a really key moment in the timeline. 

"Those are the types of things we will be trying to progress this week."