Subject to subsections (2) and (3) below, where a housing association tenancy is a weekly or other periodical tenancy, the rent payable to the housing association or, as the case may be, the housing trust or the Housing Corporation F1or the Secretary of State. . . (in this section called “the landlord”) may, without the tenancy being terminated, be increased with effect from the beginning of any rental period by a written notice of increase F2specifying the date on which the increase is to take effect and given by the landlord to the tenant not later than four weeks before that date..

Where notice of increase is given under subsection (1) above and the tenant, before the date specified in the notice of increase, gives a valid notice to quit, the notice of increase does not take effect unless the tenant, with the written agreement of the landlord, withdraws his notice to quit before that date.

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This section shall apply to a tenancy notwithstanding that the letting took place before the coming into force of this Act.

Nothing in this section shall authorise any rent to be increased above the rent limit, and any reference in section 88 of this Act to the variation by agreement of the rent recoverable under a tenancy shall include a reference to variation under this section.