New Zealand will not be immune from the fallout linked to international sanctions against Russia, Prime Minister Jacinda Ardern says. 

Earlier today the United States announced a ban on buying Russian oil. 

Ardern said New Zealand had not imported oil from Russia since January last year. 

However New Zealand would not be immune to the economic fallout from that, and other, decisions. 

Ardern was speaking to reporters before the Russia Sanctions Bill goes before Parliament today. 

The bill, which will allow New Zealand to freeze assets, target oligarchs and even shut off airspace to Russian aircraft, will be passed this week under urgency, Ardern said yesterday. 

McDonald's, Estee Lauder, Shell, Starbucks, Coca-Cola and PepsiCo have also announced they have suspended operations in Russia. 

Asked about Kiwi companies not trading in Russia, Ardern said New Zealand's business links there was relatively limited. 

Asked about comparisons to Saudi Arabia, where New Zealand continued promoting trade, Ardern said this was an opportunity to discuss issues with human rights. 

The NZ Government's sanctions announcement has been endorsed already by most parties and follows mounting calls from New Zealand's Ukrainian community to do more to stand with their home country. 

Earlier today President Joe Biden announced that the US will ban all Russian oil imports, toughening the toll on Russia's economy in retaliation for its invasion of Ukraine. But he acknowledged it will bring costs to Americans, particularly at the gas pump. 

The action follows pleas by Ukrainian President Volodymyr Zelenskyy to US and Western officials to cut off the imports, which had been a glaring omission in the massive sanctions put in place on Russia over the invasion. Energy exports have kept a steady stream of cash flowing to Russia despite otherwise severe restrictions on its financial sector. 

Russian forces have reportedly launched hundreds of missiles and artillery attacks on residential areas of Chernihiv and Mykolaiv, with Ukrainian forces also defending the port city of Odesa from invading ships. 

The Ukrainian government has accused Russia of breaking a ceasefire agreement, by shelling a route intended to allow civilians to escape the besieged city of Mariupol. 

Residents of the port city are under intense bombardment by Russian troops, and also living without heat, water, sanitary systems or phones.