11.—(1) The powers conferred by regulation 10 are—
(a)to withhold the whole or any part of the sums payable to the beneficiary;
(b)to recover on demand the whole or any part of the sums already paid to the beneficiary; and
(c)to require the beneficiary to pay to the Department an additional sum equal to no more than 10% of the sums paid or payable to him.
(2) Where the Department takes any steps specified in paragraph (1), it may also suspend or terminate the undertaking, and thereupon any entitlement of the beneficiary to payment in respect of the unexpired period of the undertaking shall likewise be suspended or terminated, as the case may be.
(3) The powers conferred on the Department by paragraph (2) shall be exercisable by a notice served on the beneficiary by post at his last known address.