Salisbury attack 'changes things', but Russia trade deal still possible - Jacinda Ardern

A deadly nerve agent attack against a former Russian spy in Britain has "changed things", but it's too early to say if it's scuppered the chance of a free trade deal with Russia, says Jacinda Ardern.

"We all agree that Salisbury changes things, and so it is too early at this point to say when or if those talks will restart," the Prime Minister told Newshub Nation on Saturday morning.

There has been widespread condemnation of the attack, which the UK, US and their European allies have blamed on Russia.

Russia has denied any involvement. Overnight, it called UK Foreign Minister Boris Johnson's claim that Russian President Vladimir Putin ordered the attack himself "shocking and unforgivable".

Ms Ardern told Newshub Nation host Lisa Owen the incident was "repugnant".

"This is a violation of international law, and now as a consequence, Salisbury has changed things."

Discussions on a free trade deal between New Zealand and Russia were suspended in 2014 when the latter invaded Ukraine, annexing the Crimean peninsula. Labour and NZ First resumed discussions after they formed the Government last year.

"In the coalition deal, it simply makes reference to working towards something," said Ms Ardern.

"What we were proposing was not inconsistent with the UK or the EU. We were not proposing to ignore the sanctions that are in place, and that is a very important point."

But with the UK and Russia pulling diplomats, relations are now frostier than at any time since the Cold War. 

UK High Commissioner Laura Clarke told RNZ's Morning Report this week that Britain was in favour of New Zealand reaching free trade deals with both the EU and the UK, but our Government has to "reach conclusions about compatibility and prioritisation" with regard to a deal with Russia.

"She's saying that in the context of Salisbury, and as I've said, the Minister of Foreign Affairs, the Minister of Trade and I are deeply concerned," said Ms Ardern. "Salisbury changes things."

The UK continued trading with Russia following the Crimea invasion, within the restrictions posed by the sanctions.

"Boris Johnson was here not so long ago talking about the $5 billion worth of trade that the UK had undertaken in that time as well… There were other elements of trading that was going on within the EU and the UK whilst fulfilling the obligations of the sanctions," said Ms Ardern.

Whether New Zealand will call off any future talks on trade with Russia remains to be seen.

"It is too early now to have any of these conversations, given the serious international situation that we are in… Our focus is on making sure that we respond appropriately to that. What is not appropriate right now is to be having a conversation about potential [free trade agreements] in the future. We've said that very clearly."

Foreign Minister Winston Peters told RNZ this week that Salisbury "somewhat complicated" talks, but that New Zealand shouldn't have to choose between Russia and Europe.

Speaking to Newshub Nation last weekend he defended Russia's human rights record, saying there was "no evidence" it was involved in the shooting down of a passenger jet in 2014 or meddling in the US election, despite widespread international acceptance Russia had a hand in both.