The Department for Transport in the UK have initiated a new multilateral agreement, M345, to allow the transport of Ammonia solution (UN 2672) in IBCs, where this would not normally be allowed due to the vapour pressure exceeding 110 kPa at 50 °C or 130 kPa at 55 °C.
M345 is quite similar to the expired multilateral agreement M256, previously initiated by Ireland, but with stricter requirements for the IBCs to be used.
The multilateral agreement, available on the UK DfT website here: https://www.gov.uk/government/publications/carriage-of-dangerous-goods-multilateral-agreement-adr-m256
has been countersigned by Ireland, as detailed on the UNECE website here: https://unece.org/adr-multilateral-agreements
The agreement is now valid for transport in the UK and Ireland, as long as the requirements of the agreement are adhered to (such as the IBCs used being tested to the required pressure) and details of the agreement entered in the transport document.
Multilateral agreements are valid for road transport only, within the countries which sign them.