Arbitration Act 1940
Statements of Claim and Defence
(1) Within the period of time agreed upon by the parties or determined by the arbitral tribunal, the claimant shall state the facts supporting his claim, the points at issue and the relief or remedy sought, and the respondent shall state his defense in respect of these particulars, unless the parties have otherwise agreed as to the required elements of those statements.
(2) The parties may submit with their statements all documents they consider to be relevant or may add a reference to the documents or other evidence they will submit.
(3) Unless otherwise agreed by the parties, either party may amend or supplement his claim or defense during the course of the arbitral proceedings, unless the arbitral tribunal considers it inappropriate to allow the amendment or supplement having regard to the delay in making it.