A new political poll has the gap between the Left and Right blocs narrowing, with both Labour and National up at the expense of the Greens and Act. 

The poll also has Jacinda Ardern as the country's preferred Prime Minister, however National's Christopher Luxon has narrowed the gap considerably. 

The Curia poll for February has Labour - up 1 percentage point - at 42 per cent, just four points ahead of National on 38 per cent. National gained 5 percentage points on January. 

Curia has historically been the polling company for the National Party. More recently the Taxpayers' Union has been sponsoring the polls. 

Act, meanwhile, dropped to 7 per cent, which Curia principal David Farrar said was the first time the company had showed the party polling below its 2020 election result. 
 
"This poll shows that not only has National stopped bleeding support to ACT, but it has started to gain back some of its former voters who voted ACT in 2020," Farrar said in an email to subscribers to the poll. 

"Of course this might just be a harsh sample for ACT, so it would be unwise to conclude this is happening until we get further data." 
 
The Green Party dropped five points to 6 per cent. 

TOP, which recently named Raf Manji as its new leader, scored 2 per cent. 

Ardern rose one point in the preferred prime minister ranking, to 39 per cent, while Chris Luxon rose 11 points to 29 per cent. 

"This is a very good result for an opposition leader outside an election campaign," Farrar said.