Article XII of the Marrakesh agreement establishing the world trade organization deals with accession.
The full text of this provision reads as follows:

“1. Any State or separate customs territory possessing full autonomy in the conduct of its external commercial relations and of the other matters provided for in this Agreement and the Multilateral Trade Agreements may accede to this Agreement, on terms to be agreed between it and the WTO. Such accession shall apply to this Agreement and the Multilateral Trade Agreements annexed thereto.

2. Decisions on accession shall be taken by the Ministerial Conference. The Ministerial Conference shall approve the agreement on the terms of accession by a two-thirds majority of the Members of the WTO.

3. Accession to a Plurilateral Trade Agreement shall be governed by the provisions of that Agreement.”

Perhaps the most striking thing about WTO Article XII is its brevity. It gives no guidance on the “terms to be agreed”, these being left to negotiations between the WTO Members and the applicant. Nor does it lay down any procedures to be used for negotiating these terms, these being left to individual Working Parties to agree. These have evolved separately as will be seen in the next section of this paper. In this, it follows closely the corresponding Article XXXIII of GATT 1947.

A number of other WTO provisions are relevant to accession — for instance:

Article XVI.1, lays down that “Except as otherwise provided under this Agreement or the Multilateral Trade Agreements, the WTO shall be guided by the decisions, procedures and customary practices followed by the CONTRACTING PARTIES to GATT 1947 and the bodies established in the framework of GATT 1947”;

Article XII:2 states that “Decisions on accession shall be taken by the Ministerial Conference”, Article IV:2 makes it clear that “In the intervals between meetings of the Ministerial Conference, its functions shall be conducted by the General Council”;

Article IX deals with decision-making. On 15 November 1995 the General Council agreed to procedures regarding decision-making under Articles IX and XII of the WTO Agreement which clarified the relation between these two provisions (WT/GC/M/8, page 6);

Article XIII provides that:

“1. This Agreement and the Multilateral Trade Agreements in Annexes 1 and 2 shall not apply as between any Member and any other Member if either of the Members, at the time either becomes a Member, does not consent to such application.

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3. Paragraph 1 shall apply between a Member and another Member which has acceded under Article XII only if the Member not consenting to the application has so notified the Ministerial Conference before the approval of the agreement on the terms of accession by the Ministerial Conference.”