A report by the , which campaigns for greater female board representation, showed that female representation on boards stands at 15.8 percent.

Only ten FTSE 100 companies have an all-male board, down from 15 last year.

Diageo leads the way in board diversity, with 44 percent female representation, including its chief financial officer, .

There are similarly encouraging trends in FTSE 250 companies, with female board representation hitting 9.8 percent, up from 7.8 percent in the last study. However, 110 companies (44 percent) still have all-male boards, although this is down from 52.4 percent.

Jane Scott, a member of the 30% Club, said: "We are encouraged to see a steady rise in the number of female directors being appointed to FTSE boards. We still have a long way to go before we reach the 30% Club's aspirational target of 30% by 2015, but monthly improvement is being made.