BioShock Infinite has sold in excess of 4 million copies, Take-Two has announced.

The title, which went on sale in March, is expected to become the highest-selling release in the BioShock franchise, according to CEO Strauss Zelnick.

Borderlands 2, released last September, has also broken the 7 million sales barrier, Zelnick revealed.

The game remains on track to become the highest-selling release in the history of 2K.

Take-Two revealed the sales figures during its FY14 Q1 earnings call this evening. The call is currently ongoing.