Marketing software group Alterian chief executive David Eldridge has resigned after a profit warning pushed its shares down by almost 20%.

Eldridge said that a major client had delayed placing an order, which was due to be signed by the end of Alterian’s financial year on 31 March.

The delay is likely to impact revenues for the financial year just ended which Alterian predicts could be 10% lower than forecast. Alterian’s shares plunged 19% to 154p after the announcement.

Alterian did not name the client. However, the company said that it was a partner that licensed Alterian’s technology to its own customers.

The company said that the contract renewal could still be signed.

"The board considers that it is likely that the contract renewal and extension will be agreed, but cannot be certain that this will happen, or of the timing of it happening," the company said.

Eldridge said, "The results for the year will be disappointing, principally as a result of the deferral of a major expected contract renewal and extension."

"I take my responsibilities seriously and am stepping down from my role as the chief executive of Alterian."

The next update from the company is expected to be on 18 April.