Watch: Steven Joyce on his political legacy as he announces his retirement from Parliament

National's long-serving MP Steven Joyce has announced his retirement from Parliament today.

Mr Joyce was first elected as an MP in 2008. He's leaving after missing out on National's leadership race last month to Simon Bridges.

"I have had a wonderful time in this place over the last nearly ten years including nine years as a Minister, and have been privileged to be able to make a real contribution to the development of our country," Mr Joyce said in a statement released this afternoon.

"With the recent change of National Party leadership I have had the opportunity to consider again what I would like to do over the next several years."

Mr Joyce also revealed that he had been offered a senior role under the new leadership of Mr Bridges.

"Simon has made a very positive proposal to me to stay and contribute as a senior member of the team on the front bench with a choice of portfolio.

"However I feel that it is time for him to get a new team around him to take National forward and win in 2020 and then govern again for the benefit of all New Zealanders.

"I have offered to assist in any way I can from outside parliament and will remain a staunch supporter of the Party."

Mr Joyce said personal highlights of his political career were "setting up major infrastructure projects like ultrafast broadband, the major motorway and expressway projects now coming on stream, and the electrification of Auckland’s commuter rail network".

New National Party leader Simon Bridges was quick to thank Mr Joyce for his service to New Zealand and the National Party.

"He played a major role in rebuilding the National Party, leading the past five elections and helping turn National into New Zealand's largest and most popular political party.

"Steven is a huge loss to Parliament and to the National Party and I want to thank him for his immense contribution to New Zealand, and his wife Suzanne and their children for sharing them with us. We wish him all the best."

Below is 1 NEWS NOW live updates as National Party MP Steven Joyce fronted media after announcing that he will retire from Parliament.

2:55pm:  That wraps up his media address, now begins the political fallout from his decision!

When asked who he would like to be offered the National Party finance portfolio, Mr Joyce said it wasn't his place to answer.

2:52pm:  Mr Joyce says his family has been very supportive of his decision and will be expecting more vegetables out of the garden now.

2:48pm:  "The only regret I have is having Labour unpick some of last year's budget.

"The tax rate is untenable for people on the average wage," Mr Joyce says.

2:45pm:  Mr Joyce says he had to work hard to get an international presence.

The comment was made in reference to the infamous dildo throwing incident at Waitangi which made worldwide headlines.

"The whole thing has been an absolute blast," he says.

2:43pm:  His retirement from Parliament will take place after the next session in the House where he will give a valedictory speech.

2:38pm:  Mr Joyce says he fully supports Simon Bridges and expects him to be Prime Minister in 2020.

He also says he doesn't regret running for the National leadership.

2:37pm:  Mr Joyce confirms he wasn't offered the Finance Portfolio, but says that didn't influence his decision.

He says now he can spend more time with his family.

2:35pm: Mr Joyce has begun his address:

"I have been very lucky to have nine and a bit year in this Parliament and hopefully make a contribution to this country."

2:32pm:  New National leader Simon Bridges has wished Mr Joyce the best and thanked him for his service.

2:30pm: Click here for the live stream of Mr Joyce's media stand-up.