The controversial move is the first attempt by a mortgage lender to give customers an incentive to by-pass brokers, who are paid commission on every mortgage sold. It comes as Bank of Scotland is spending 160m to build a network of 46 branches around the country. The brokers are set to air their concerns at the meeting with bank executives on Tuesday.

The row broke out last week when the bank unveiled plans for a major assault on the mortgage market by offering deep discounts to borrowers who switch from other lenders. The discounts last for two years when the mortgage is arranged directly with the bank, but just one when arranged through a broker.

Bank of Scotland has also snubbed brokers by deciding that a new 100% mortgage for first-time buyers, with interest-only payments for up to two years, will only be offered to borrowers who deal with it directly.

"We're surprised and disappointed at the differential in the product range offered to brokers, " said Michael Dowling, president of the Independent Mortgage Advisers' Federation. "We didn't expect that, after Bank of Scotland launched its branch network, the broker would lose out."

At least 90% of the bank's 3bn mortgage book had come through brokers, Dowling added.

A bank spokesman said customers expected something more when they deal with it directly. "People coming to us directly want different features to people who come to us through brokers, " he said.

Uniquely in the mortgage market, Bank of Scotland is offering the discounts to both existing and new customers.

This means home owners on the bank's standard variable rate of 3.49% can switch to a discounted rate as low as 2.7% for the next two years, before moving back again.