Companies with all-male boards will come under fresh pressure to hire women directors under boardroom guidelines to be published today...The new UK Corporate Governance Code will also force directors to submit to annual shareholder elections and for the first time obliges large boards to be appraised by outside experts...The code states for the first time that listed companies, when searching for, or appointing directors, must “pay due regard for the benefits of diversity on the board, including gender”...Of Britain’s 100 biggest listed companies, 25 are without female representation on the board, according to a study by the Cranfield Business School. They included ABF [Associated British Foods], BAE Systems, International Power, Rentokil Initial and Royal Bank of Scotland.