general willingness to tolerate even appreciable pollution harm, provided - and this is an important proviso -that the watercourse State of origin is making its best efforts to reduce the pollution to a mutally acceptable level. u/ A requirement that existing pollution causing such harm be abated immediately could, in some cases, result in undue hardship, especially where the detriment to the watercourse State of origin was grossly disproportionate to the benefit that would accrue to the watercourse State experiencing the harm. l,Q$/ On the other hand, failure of the watercourse State of orjgin to exercise due dlliqence in reducing the pollution to acceptable levels would entitle the afPected State to claim that the State of origin had breached its obligation to do so. (5) Like article 22, paragraph 2 of article 23 requires that the measures in question be taken “individually or jointly”. The remarks made in paragraph (4) of the commentary to article 22 apply, vi.& with regard to paragraph 2 of article 23. Thus, the requirement that watercourse States act “individually or jointly” to prevent, reduce and control water pollution is to be understood as moaning that joint, co-operative action is to be taken where appropriate, and that such action is to be taken on an equitable basis. As explained in the commentary to article 22, the obligation to take joint action derives from certain general obligations contained in Part II of the draft articles. In the case of paragraph 2 of article 23, the obligation of watercourse States under article 6 to “participate in the . . . protection of an international watercourse [system] in an eqllitable and reasonable -manner”, as well as that under article 9 to “co-operate .., in l9.3.1 See the Fourth report of the Special Rapporteur (A/CN.4/412/Add.2),
**Analysis**
The text appears to be discussing international law and cooperation regarding the protection of international watercourses, including the prevention, reduction, and control of water pollution. The language used suggests a focus on environmental protection and international cooperation, rather than economic development or industry-specific issues. The text also touches on the concept of "due diligence" and the obligation to take joint action, which implies a sense of responsibility and cooperation between countries.

**Category**
Natural resources and environment, International trade