The figure, which has not changed for the last three years, is from BSA's Global Software Piracy Study.

The BSA says many UK firms still ignore software licensing regulations, despite Government and industry efforts to enforce the licensing laws.

A spokeswoman said:

"The UK remains in a situation where almost one out of every three software installations is illegal.

"This is costing the software industry billions of dollars and putting UK businesses at risk. Despite attempts to educate businesses, and increased efforts to enforce the licensing laws by the government and the industry, it is clear that more must be done."

The report also found increasing number of small firms went online to download illegal software.