MPs are to investigate the gap between the pay of men and women as a new row broke out yesterday over equality.

The Trade and Industry Select Committee called for written evidence after announcing a fresh probe into the 18% difference.

The committee said one of the main problems in promoting equal pay was that many of the higher paid jobs tended to be dominated by men.

Meanwhile Amicus said families would have £7,600 less to spend this year because organisations like the CBI were protecting companies which failed to deliver equal pay for women.

Average family income was £7,600 lower than it would be if employers were forced to carry out equal pay audits, the union claimed.

Equalities officer Linda McCulloch said: "There is a disgraceful pay gap between men and women workers which impacts on families."

The CBI denied it was the Ebenezer Scrooge of the labour market and said it agreed that unfair discrimination should be stamped out.

Deputy director general John Cridland, said: "Too much of the argument about the gender pay gap has been too simplistic.

"We mustn't get hung up on discrimination by employers. That is only a small part of this problem.

"Much more important are the career choices women make which leave them concentrated in lower paying sectors and women's traditional caring responsibilities which restrict their options and interrupt their careers."