The government on Friday vowed to use the revenue from the envisaged "departure tax" only to boost tourism, amid concerns the money would be directed toward other purposes.

Starting Jan. 7, 2019, the implementation of the departure tax will require each passenger, regardless of nationality, to pay ¥1,000 ($9) when leaving Japan by air or sea.

The revenue will be allocated for achieving three main goals — creating an environment for pleasant and stress-free journeys, facilitating access to information regarding tourist attractions, and improving visitor satisfaction levels by preparing resources tailored to each region's unique culture and environment — the basic policy for the levy says.

"We plan to allocate funds to policy programs that are forward-looking and cost-efficient and turn Japan into a country which people across the globe would want to visit," Prime Minister Shinzo Abe told a meeting of Cabinet ministers who adopted the criteria.

According to the plan, toddlers under 2 and passengers in transit who leave Japan within 24 hours of arrival will be exempt from the tax. The government still needs Diet approval to introduce what is officially known as the tax on international tourists.

Buoyed by a tourism boom that has produced a new annual record of over 24 million visitors as of November, Japan aims to reel in 40 million overseas tourists in 2020 when Tokyo hosts the Olympics and Paralympics.

The figure for 2017 is expected to top 28 million.

In the draft fiscal 2018 budget approved Friday, the government plans to use an estimated ¥6 billion in revenue from the departure tax for urgent projects, such as making more multilingual services available.

Still, some taxpayers have voiced skepticism, saying it is not clear how they will benefit from a tax that is primarily designed to offer better services for foreign tourists.