MANILA, July 9 (Reuters) - The defence minister of the Philippines on Thursday rejected as "baseless" and "ludicrous" assertions by Chinese scholars that its northernmost island-chain province belongs ‌to Beijing, calling the claim concerning and worthy of challenge.

Chinese state-run news site ‌GDToday reported on July 2 that scholars from institutions including Nanjing University argued at a June 30 symposium ​that Batanes was a natural extension of Taiwan and therefore belonged to China.

Beijing has not formally endorsed that position.

The assertions may add a new dimension to long-running tensions between Manila and Beijing, which are already embroiled in multiple disputes over islands and features in the South ‌China Sea.

"I view this, once ⁠again, as probably a signal of a preconceived intention," Defence Secretary Gilberto Teodoro told reporters.

"It is not far-fetched to think that this is ⁠already part of their plan. And it also validates what we have been saying that they have a plan to control the entire Pacific Ocean."

"What is this for, right? And we know ​this ​is baseless. This is nonsense. It is ludicrous," ​he said. "So this is concerning, and ‌it is something that must be challenged," he added, but did not elaborate.

The Chinese embassy in Manila did not immediately respond to a Reuters request for comment on Teodoro's remarks.

Batanes, home to about 20,000 people, is about 160 km (100 miles) south of Taiwan along the strategically important Luzon Strait, a key passage linking the South China Sea and the ‌Pacific Ocean.

It has become increasingly important in security planning ​and has hosted joint military exercises involving Philippine ​and allied U.S. forces.

Beijing previously sanctioned Teodoro ​and his close relatives over what it said were "erroneous remarks" made about ‌China.

The scholars' comments came weeks after the ​Philippines and Japan announced ​in May they would begin formal talks on delimiting the maritime boundary of their exclusive economic zones and continental shelves in accordance with international law, a move ​China criticised.

Beijing claims almost ‌the entire South China Sea, a strategic waterway through which more than $3 trillion ​in trade passes annually, despite a 2016 arbitral ruling that invalidated those claims.

(Reporting ​by Nestor Corrales; Editing by Martin Petty)