As Reuters informs us:
The World Trade Organization's 164 members commit to treating other members equally so they can all benefit from each other's lowest tariffs, highest import quotas and fewest trade barriers for goods and services. This principle of non-discrimination is known as most favoured nation (MFN) treatment. [...]
There is no formal procedure for suspending MFN treatment and it is not clear whether members are obliged to inform the WTO if they do so.
India suspended Pakistan's MFN status in 2019 after a suicide attack by a Pakistan-based Islamist group killed 40 police. Pakistan never applied MFN status to India.
Both India and Pakistan appear to have joined the WTO in 1995. And both countries seem to have been GATT members (precursor to WTO) since 1948.
So, how comes Pakistan never granted India MFN? 25 or so years seems like a long time to not implement a treaty. (And even more if counting from GATT joining.) Was there any litigation (through WTOs dispute resolution) related to this? Or did Pakistan invoke the sanctions-related exceptions in the WTO/GATT treaties, and India didn't contest this?