Jacinda Ardern lands in San Francisco as she prepares to return to Washington DC for meeting with President Joe Biden

The Prime Minister has just touched down - again - in San Francisco as she makes her way back to Washington DC for her meeting with US President Joe Biden next week.

Top of Jacinda Ardern's meeting agenda wishlist are trade, climate change, and the Ukraine conflict.

Since the horrific massacre in Uvalde, Ardern has been balancing on a highwire above America's charged gun reform debate.

She and New Zealand are seen by many there as the guiding light for gun control in response to March 15. Senator after congressman after governor after president of Microsoft have praised Ardern for swiftly getting semi-automatics banned.

But as the leader of a small country attempting to secure a trade deal, Ardern has not - because she cannot - told America, the land of the free, what to do.

The closest she's come is to say "change is possible" and to put weight on the words "banning semi-automatic weapons" when speaking of New Zealand's experience.

But while she says that on the world stage, at home there's a shocking spate of shootings.

When asked on Saturday whether New Zealand's gun reforms were actually working, Ardern said: "We've moved on one part of our problem but that does not mean the problem has evaporated - not at all.

"That's why you'll see us for instance continuing with - for instance - the important implementation of the gun register," Ardern continued.

"The police themselves acknowledge this will be an important part of making progress on gun issues in New Zealand."

After wrapping the original United States itinerary in Seattle, Ardern is now in a holding pattern and is waiting for that White House meeting on Tuesday (local time).

She's now in San Francisco, and will then travel on to Washington DC.