NEW DELHI • US Secretary of State Mike Pompeo and Pentagon chief James Mattis are heading to New Delhi next week for an inaugural set of high-level meetings - one more sign that the West wants to deepen cooperation with India as a hedge against China.

But former Indian officials say an understaffed Foreign Ministry is holding back Prime Minister Narendra Modi's plan to seek greater global influence in line with the country's fast-growing US$2.6 trillion (S$3.6 trillion) economy.

The nation of 1.3 billion people deploys only around as many diplomats as New Zealand, which has a population of around 5 million.

"We're woefully under-equipped," said former junior foreign minister Shashi Tharoor, who chairs India's parliamentary committee on foreign affairs. "This is not worthy of a country of India's size and ambition."

The need for a well-staffed Foreign Ministry in New Delhi is growing only more urgent, particularly as US President Donald Trump's administration emphasises outreach to the Indo-Pacific region in a bid to elevate India as a counterweight to China.

New Delhi has started to take a leading role in pushing back against China's Belt and Road Initiative, which is encroaching on India's South Asian backyard.

India also has many unfinished goals. It is angling for a permanent seat on the United Nations Security Council and membership in the Nuclear Suppliers Group, while trying to defend the global mobility of its IT workers overseas as protectionism rises.

With roughly 940 foreign service officers, India has one of the most understaffed diplomatic corps of any major country - just slightly higher than New Zealand's 885 officers, or Singapore's 850.

India is vastly outnumbered by the Japanese and Australian services of around 6,000 people, the estimated 7,500 diplomats of China and the US State Department's service of nearly 14,000.

The Indian Foreign Ministry is aware of the shortage and it is working to bolster staffing, according to a government official.

It has increased recruitment to around 35 new officers annually and borrowed defence and economic experts from other ministries, the official said.

In 2016, the ministry said it was still 140 officers short of its sanctioned strength of 912 diplomats.

Many Indian embassies also have only one ambassador and one other international diplomatic-rank officer, leading to functions being performed by lower-level or local staff who are "under-qualified to perform them", said Mr Tharoor.

The shortage is particularly pronounced at a time when Mr Modi has increased his foreign travel, having already visited nearly 60 countries in just four years. But thin staffing makes it difficult for India to follow up on his headline-generating outreach.

BLOOMBERG