BANGKOK (Reuters) - Thai Prime Minister Prayuth Chan-ocha said on Friday his military-backed government aimed to broaden the tax base in the new fiscal year beginning next month, bringing in an inheritance tax among other changes.

In his first speech to an appointed parliament since seizing power in a military coup in May, the army chief, who became premier in August, gave no indication on how long he would stay in power to push through planned reforms.

During a wide-ranging, two-hour address, Prayuth said that only 20 million people out of Thailand's population of about 68 million paid taxes.

"The tax collection in this new fiscal year will be broadened to new tax bases to boost revenue to the country and promote fairness. This will include an inheritance tax and land tax," he said.

"The tax issue is aimed at promoting fairness, with a limited impact on low-income earners ... Those tax (benefits) that favor the rich will be terminated," he added.

He has said that a general election could be held late next year, after a reform of the electoral system, although some political analysts believe he could be in power longer.

Prayuth is due to step down as army chief this month as he has reached the mandatory retirement age of 60, but the junta that seized power in May remains in place alongside the cabinet and he will continue to lead it.

Some of the broad policies he has outlined, such as a reform of the electoral system, mirror the demands of the Bangkok middle class and royalists who protested for months against the government of former Prime Minister Yingluck Shinawatra, which was overthrown in the coup.

On Friday, Prayuth stressed his support for the monarchy but said Thailand had no class system. "We are all just Thai."

Flitting from subject to subject, as he has done during his televised addresses to the country each Friday evening, Prayuth touched on human trafficking, the need to improve the education system and why healthcare should focus on the prevention of disease as much as its treatment.

He frequently veered away from affairs of state that might normally dominate such a policy speech, at one point telling those in charge of the train line linking Bangkok's main airport to the city center to speed up repairs.

"You complain there aren't many people using the airport link but if people start coming, it's broken. Go and fix the airport link and hurry up about it," he said.

He also brought up a recent scandal involving a beach vendor who chased away a Russian tourist because she refused to rent a sun-lounger from him, filmed and widely viewed on social media.

"Don't let it happen again, kicking sand in the faces of sitting tourists. What are you even thinking? I don't understand. We should do something with these people. Maybe shove sand down their throats."


(Reporting by Panarat Thepgumpanat and Viparat Jantraprap; Writing by Alan Raybould; Editing by Richard Borsuk)