An Indian national flag flutters on top of the Indian parliament building in New Delhi December 1, 2010.
An Indian national flag flutters on top of the Indian parliament building in New Delhi December 1, 2010. Reuters / B Mathur

India, which is trying to expand its influence in Sri Lanka amid the island's economic troubles and is worried that China is also making inroads, said on Thursday it was aware of reports about the planned visit of a Chinese vessel to Sri Lanka's Hambantota port, which was built with money from Beijing.

Shipping data from Refinitiv Eikon showed research and survey vessel Yuan Wang 5 was en route to the southern Sri Lankan port and was expected to get there on Aug. 11.

"The government carefully monitors any developments having a bearing on India's security and economic interests, and takes all necessary measures to safeguard them," India's foreign ministry spokesperson, Arindam Bagchi, told a weekly media briefing.

"I think that should be a clear message."

He did not say what measures India was taking and who the message was addressed to.

China's foreign ministry did not immediately respond to a request for comment. Sri Lankan officials could not immediately be reached for comment.

A Sri Lankan government official told Reuters on condition of anonymity that Indian diplomats in Colombo lodged a verbal protest with the Sri Lankan foreign ministry on Monday.

A Sri Lankan consulting firm, the Belt & Road Initiative Sri Lanka, says on its website that Yuan Wang 5 will be in Hambantota for a week.

"The vessel will conduct space tracking, satellite control and research tracking in the north-western part of the Indian Ocean region through August and September," it says, without citing a source.

Sri Lanka formally handed over commercial activities in its main southern port to a Chinese company in 2017 on a 99-year lease after struggling to repay its debt. The port is near the main shipping route from Asia to Europe.

U.S. and Indian officials have worried that the $1.5 billion port could become a Chinese military base.

China is one of Sri Lanka's biggest lenders, but as the island nation faces its worst economic crisis in seven decades, India this year alone has provided it support of nearly $4 billion.

India's concerns come amid tensions with China elsewhere.

U.S. President Joe Biden and China's Xi Jinping will hold their fifth call as leaders on Thursday, as concerns rise over a possible visit to Chinese-claimed Taiwan by U.S. House Speaker Nancy Pelosi.

Taiwan's military fired flares on Thursday to warn away a drone that "glanced by" a strategically-located and heavily fortified island close to the Chinese coast that was possibly probing its defences, the Taiwanese Defence Ministry said.