April 3 (Reuters) - AI video startup Runway said on

Thursday it had raised $308 million in a new funding round, led

by private equity firm General Atlantic, to expand its new media

ecosystem.

The latest funding round valued the New York-based company

at over $3 billion, Bloomberg reported, citing people familiar

with the matter.

Runway, however, declined to comment in reference to the

valuation.

With the latest fundraise, the startup plans to develop AI

research for new media focusing on its AI film and animation

studio using world simulators.

A world model is an AI system that builds an internal

representation of an environment, and uses it to simulate future

events within that environment.

The round also saw participation from SoftBank Group

, Nvidia ( NVDA ), Fidelity Management & Research

Company and Baillie Gifford.

Runway, which offers software that allows users to create

videos by using text prompts or images, signed a deal with

Lionsgate last September to create a customized video generation

model to help "filmmakers, directors and other creative talent

augment their work".