A law professor says New Zealand's deployment of troops to the Red Sea is a good first step.

The Government last week announced six Defence Force personnel would be deployed to support military action against Houthi militants.

Waikato University law professor Alexander Gillespie, says our actions are justified, but we need to be wary of possible escalation.

"One of the risks right now is that it appears that people think they're going up for one reason, when in fact it's something else. So we have to maintain as much as we can in clear, independent foreign policy- and take each step very carefully."

Earlier today, 36 targets in Yemen were hit in a joint US-UK airstrike, a day after the US hit more than 85 targets in Iraq and Syria.

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