日本語道場 — Nihongo Dojo

～上は

~ta ue wa

now that, since (formal)

When to use it

Use ～上は in formal writing or set speeches to mean "now that (something has been decided/done), it follows that...". It signals that an irreversible step has been taken, so the speaker accepts the resulting obligation or resolve — hence it pairs naturally with しかない・ほかない・つもりだ・～たい and volitional endings. In everyday conversation this sounds stiff; native speakers reach for ～からには or ～以上は instead.

Formation

Verbs: plain past + 上は (引き受けた上は、決まった上は). Non-past dictionary form is possible but rare and reads archaic (会社を代表する上は). Never with ～ている or polite forms.
i-adjectives: not used.
na-adjectives: not used (use ～以上は: 不可能である以上は).
Nouns: not used directly; ～である以上は covers that sense.
Note: the clause after 上は expresses resolve, obligation or a natural consequence — not a plain description of fact.

Examples

Now that we have signed the contract, we will absolutely meet the deadline.
Having taken on this project, I'll see it through to the end.
Now that it has come to this, there is nothing to do but report it to the board.
Now that it has been decided internally, the policy cannot be changed.
Having put forward the proposal, we will handle it responsibly.