The Middlesex-based company is Europe’s largest and the world’s second-largest frozen-food manufacturer, with sales of £1.1bn last year.
Nomad co-founder Martin Franklin said: "There are a lot of opportunities for further acquisitions in the [frozen food] market."
British Growers chief executive Jack Ward said: "Birds Eye is a well-established brand and a very important customer for British producers, especially for the frozen vegetable sector.
He added: "They may see opportunities in branded niche consumer foods, or may simply have seen an undervalued company that they can sell on in a couple of years. I can’t think that they would want to jeopardise what they have."
Permira acquired the Iglo and Birds Eye brands from Unilever in 2006.