Japanese telecom and investment giant Softbank just made sure Flipkart has plenty of cash to fight off Amazon's aggressive push into India.

The firm poured $2.5 billion into the e-commerce giant in what the company claims is the biggest ever private funding deal for a tech company based in India.

The move comes after Microsoft, Ebay, and Chinese tech giant Tencent all lined up behind Flipkart with a then-record-breaking $1.4-billion investment of their own earlier this year. Between the two infusions, Flipkart now has a war chest of around $4 billion.

"Very few economies globally attract such overwhelming interest from top-tier investors," Flipkart co-founders Binny and Sachin Bansal said in a joint statement. "It is recognition of India’s unparalleled potential to become a leader in technology and e-commerce on a massive scale."

Excited to welcome Softbank Vision Fund as a long-term partner in @Flipkart!A true recognition of India’s potential https://t.co/yGoGUEpOzz — binnybansal (@binnybansal) August 10, 2017

It may need every penny of that arsenal. Amazon CEO Jeff Bezos has decided India is the company's top prospective market abroad and pledged more than $5 billion to expansion efforts there.

Terrific meeting with @narendramodi. Always impressed, energized by optimism and invention in India. Excited to keep investing and growing. https://t.co/xhQ58dik3y — Jeff Bezos (@JeffBezos) June 25, 2017

Softbank, a prolific tech investor thanks to its massive $100 billion Vision Fund, previously backed Flipkart rival Snapdeal and tried to broker a merger between the two companies before talks ultimately fell through last month.

“India is a land of vast opportunity," SoftBank CEO Masayoshi Son said in a statement. "We want to support innovative companies that are clear winners in India."

Softbank's investment fund, which is now one of Flipkart's biggest shareholders, is also backed by the government of Saudi Arabia, Apple, Qualcomm, and manufacturing heavyweight Foxconn, among others.

Flipkart also recently took over Ebay's operations in India as part of the investment deal.

Meanwhile, Amazon has been making moves of its own. It successfully introduced is discount extravaganza Prime Day in the country last month and recently won approval from the Indian government to start selling groceries.