UPDATE: IRTA's Mike Trimby confirms there has been 'some interest' from Vietnam for a MotoGP, but 'still a long way to go'.

Sepang CEO Razlan Razali is happy to see MotoGP expand in Asia, as long as they can keep the penultimate round of the season.

Aside from episodes in Indonesia 1996-1997 and China 2005-2008, Malaysia and Japan have been the only Asian countries constantly on the Motorcycle Grand Prix calendar since 1991.

But demand from fans and manufacturers saw the arrival of Thailand in 2018, with a planned return to Indonesia in 2021 and ongoing talks with other countries in the region.

"The good thing about Carmelo [Ezpeleta] and Dorna is that they tell me in advance which are the races coming on board for Asia," Razali said.

"I told him that’s fine if you want Indonesia to come in, or we had Thailand. He’s talking about, I think, Vietnam.

"It’s great for the sport. We need to support whatever effort is being done to make sure that MotoGP remains relevant, remains great."

To avoid diluting spectator attendance, the Thai race has been placed just before the late-season flyaway sequence of Japan-Australia-Malaysia.

But Razali doesn't mind if in future other South East Asian races are held directly before Sepang - a sold-out event in recent seasons - providing Malaysia continues as the penultimate event, followed only by the traditional Valencia finale.

"To me, it doesn’t matter as long as we are the penultimate race," said Razali, who is also principal of Sepang's MotoGP, Moto2 and Moto3 teams.

"We want to be the penultimate race because I am protecting my Malaysian fans. They can go to Thailand. They can go to Indonesia. They can go to Vietnam or anywhere else in the world, but don’t tell me when it comes to Malaysia you don’t go!"

To compensate for the travel burden caused by the race calendar expanding beyond its current 19-rounds (Finland is on course for a 2020 debut) more test sessions are due to be dropped.

Sepang currently hosts the opening official test of each year, a status Razali expects to keep.

"I think [having] the first test is important," he said. "There will still be a test [in future], especially for the rookies and I am confident that Sepang will remain the best circuit for testing.

"That’s the feeling I got from the manufacturers. They said it’s important for the official test to be in Sepang, so I’m pleased about that."