| Country | Action | Action Date | Effective Date |
|---|
| BELGIUM | Signature | 05/04/1946 | |
| BELGIUM | Ratification | 09/05/1951 | |
| DENMARK | Signature | 05/04/1946 | |
| DENMARK | Ratification | 11/04/1947 | |
| FRANCE | Signature | 05/04/1946 | |
| FRANCE | Ratification | 19/01/1949 | |
| GERMANY FEDERAL REPUBLIC | Accession | 11/06/1954 | |
| ICELAND | Signature | 05/04/1946 | |
| ICELAND | Ratification | 07/09/1951 | |
| IRELAND, REPUBLIC OF | Signature | 05/04/1946 | |
| IRELAND, REPUBLIC OF | Ratification | 02/01/1950 | |
| NETHERLANDS THE | Signature | 05/04/1946 | |
| NETHERLANDS THE | Ratification | 10/01/1948 | |
| NORWAY | Signature | 05/04/1946 | |
| NORWAY | Ratification | 21/07/1947 | |
| POLAND | Signature | 05/04/1946 | |
| POLAND | Ratification | 22/01/1947 | |
| PORTUGAL | Signature | 05/04/1946 | |
| PORTUGAL | Ratification | 13/07/1950 | |
| SOVIET UNION | Accession | 12/03/1958 | |
| SPAIN | Signature | 05/04/1946 | |
| SPAIN | Ratification | 05/02/1953 | |
| SWEDEN | Signature | 05/04/1946 | |
| SWEDEN | Ratification | 07/08/1946 | |
| UNITED KINGDOM | Signature | 05/04/1946 | |
| UNITED KINGDOM | Ratification | 01/07/1946 | |