Both versions allow 10 per cent capital repayments each year without penalty, are available up to 80 per cent loan to value and there is no higher lending charge.
Jeff Kirk, corporate relationship manager, said "The take up on our self-cert mortgages has been excellent and the products, combined with the service we offer, confirms that clients like what we are offering.
"We are firmly committed to this market and we have extended the dates on these products which offer clients, who may have income derived from a variety of different sources or do not fit conventional mortgage underwriting criteria, even greater choice."
