expression
on the occasion of; at the time of; when
Formal expression used to introduce the occasion or time when something happens. Often used in speeches, announcements, and formal writing. Similar to に際して and にあたって.
See also: に際して · に当たって (にあたって)
開会にあたり、一言ご挨拶申し上げます。
On the occasion of the opening, I would like to say a few words.
新年にあたり、皆様のご健康をお祈りいたします。
At the start of the new year, I wish you all good health.