May 9 (Reuters) - French startup Mistral AI is nearing a deal to raise about $600 million of funds to nearly triple its valuation to $6 billion, the Wall Street Journal reported on Thursday.

Existing investors General Catalyst and Lightspeed Venture Partners are likely to be among the main investors in the funding round, the report said, citing people familiar with the matter.

In February, Microsoft invested $16 million in Mistral and partnered with them to make the startup's artificial intelligence models available through the Azure cloud computing platform.

Mistral was last valued at 2 billion euros ($2.15 billion) in a funding round in December last year.

Mistral, General Catalyst and Lightspeed Venture Partners did not immediately respond to requests for comment.

($1 = 0.9319 euros) (Reporting by Dagmarah Mackos; Editing by Mrigank Dhaniwala)