WELLINGTON (REUTERS) - Hours after New Zealand imposed a nationwide lockdown to beat a coronavirus pandemic, Prime Minister Jacinda Ardern took to Facebook, livestreaming in a sweater from bed, to "check in" on citizens and tell them of the day's events.

Ms Ardern's news conferences for more than 30 minutes a day, taking queries, streaming Facebook videos and posting pictures on Instagram, offer a contrast with some world leaders who have stumbled through confusing briefings about virus combat plans.

"I thought I would jump online quickly and check in with everyone... as we all prepare to hunker down for a few weeks," she said in one of her social media messages, seen and cheered by millions in lockdown.

"This feels like the comfort of being tucked into bed at night by my mum," said a viewer who responded to the post. "Thanks for checking in with us."

New Zealand's tally of 589 virus infections and one death is far smaller than other countries, such as giant neighbour Australia, which has 4,200 cases and 17 deaths.

Last Thursday's (March 26) lockdown is expected to have far-reaching effect on the export-oriented economy of the nation of five million.

But the 39-year-old prime minister's clear communication has garnered praise, even from her fiercest critics.

"I think she communicates really clearly and really well," Mr John Key, a former prime minister and senior leader of the opposition National Party said on a radio show.

While urging New Zealanders to keep to their own "bubble", or stay home to save lives, Ms Ardern has also talked about working from her office, spending time with family, and even a struggle with toilet training her daughter, who turns two in June.

Ms Ardern took the helm of the Labour-led government in October 2017, as the youngest female prime minister at the time, and became only the second elected leader to give birth while in office, after Pakistan's Benazir Bhutto.

Her compassionate yet decisive actions after last year's mass shooting at two Christchurch mosques drew global praise.

But facing domestic criticism for her government's handling of housing shortages and the economy, Ms Ardern is expected to face a tough re-election contest in September.

On Instagram on Sunday, she described events in her "bubble", and was asked how toilet training was going with daughter Neve Te Aroha, who was three months old when she accompanied Ms Ardern at her United Nations debut in 2018.

"We are having zero success!" Ms Ardern replied.