Just one day after Flipkart disclosed that it had raised a massive $1 billion round, Amazon has upped the ante by announcing that it will invest $2 billion in its Indian marketplace, which it launched about a year ago. “At current scale and growth rates, India is on track to be our fastest country ever to a billion dollars in gross sales,” Amazon founder Jeff Bezos said in a statement.

Amazon and Flipkart are both competing for the attention of India’s 243 million Internet users and a larger slice of the country’s e-commerce market, which grew 88 percent in 2013 to $16 billion and is expected to hit $56 billion by 2023.

Flipkart, which says it has close to 22 million registered users and makes 5 million shipments per month, claims to be “India’s largest e-commerce marketplace,” while Amazon, which has not yet disclosed its user numbers for the site, says its Indian marketplace has “grown to be India’s largest store with over 17 million products.”

The timing of Amazon’s announcement is the latest sign of a fierce rivalry between the two businesses. Earlier this year, Flipkart bought online fashion retailer Myntra to help it scale up faster against Amazon.

Another key player in India’s e-commerce landscape is Snapdeal, which is backed by eBay and has raised $435.7 million in funding so far.