Britain on Tuesday encouraged New Zealand to join the fight against the Islamic State group.

During a visit to Wellington, British Foreign Secretary Philip Hammond told reporters that Britain would "very much hope" New Zealand would become an active participant in the coalition of nations fighting the militant group in Iraq.

"I know there's a debate going on within New Zealand about how New Zealand should make that contribution, and every nation in the coalition is making its contribution in a different way," he said. "Frankly, we've got used to New Zealand being there alongside us, alongside the U.S., the U.K, Australia, as part of the family."

He said New Zealand has capable armed forces that can easily work alongside troops from the U.K., the U.S. and Australia. He said Iraq is not asking for other countries to fight its war for it but rather is seeking help from them to train troops and give them air cover.

"We would very much hope that New Zealand will be an active participant in a fight which is all of our fight," he said.

Hammond said the militant threat was worldwide and New Zealanders faced a threat not only in their homeland but also when they traveled abroad.

New Zealand in November announced it was sending military planners to evaluate its options in Iraq. Prime Minister John Key said his government intends to make a decision this month about what role to play.

Key told reporters this week that he thought New Zealand needed to do something to help confront the group.

"This is an organization that has used children to behead people," he said. "They've thrown gay people off building structures. They're out there murdering people."