"All these areas are the areas China is focusing on developing right now where New Zealand also happens to be very competitive."
Speaking about the FTA China has just signed with Australia, Mr Xi said: "We don't have to have any worries about it."
Since New Zealand's FTA with China in 2008, trade have increased at 20 per cent a year.
"China has 1.3 billion people and our market is huge," Mr Xi said.
" Fine quality products from New Zealand ranging from dairy produce, wool, beef and seafoods are highly popular among Chinese consumers.
"So worries that New Zealand does not have a market for its products in China are totally unnecessary. On the contrary. Possibly New Zealand might have to worry about the fact there is more Chinese demand than you can possibly supply."
Mr Key said the relationship was "dynamic and forward looking."
There was still room to grow and he was confident two-way trade would reach the new target of $30 billion by 2020, a target set in March this year.
Reporters were given only two questions to ask of the leaders and in a deal between leaders' offices, a New Zealand report could ask only Mr Key a questions and a Chinese reporter would ask Mr Xi a question.
When Mr Key was asked for his views on democratic reform in China he said New Zealand would support China in whatever political system it chose.
"We in New Zealand acknowledge there are many different political systems around the world and in the end whatever system China ultimately rests on, in my view it will be a matter for the people of China. They will decide what system is the most appropriate for them and whatever system they have, we will support them in that."
Ministers of both countries signed 10 agreements that officials have been working on, some meaty and some just statements about engaging in closer co-operation in areas, such as the Antarctic.
The initiatives signed today were:
- A television co-production agreement allowing programmes co-produced by New Zealand and Chinese companies to be officially broadcast on Chinese TV, where potential viewing audiences are huge.
- Easing immigrations procedures for holders of Platinum and Diamond UnionPay credit cards - in lieu of employment and funds documentation.
- An extension extend the China working holiday scheme, which will enable Chinese working holiday makers to work for the same employer for up to six months.
- An arrangement on the mutual recognition of academic qualifications in higher education.
- Establishing a Food Supervisory and Traceability Cooperation Programme between the New Zealand Ministry for Primary Industries and the China Food and Drug Administration.
- An arrangement between the Ministry of Business, Innovation and Employment and the China National Tourism Administration to improve the tourist experience in both countries.
- A new partnership between New Zealand Trade and Enterprise and the China Chamber of Commerce of Foodstuffs and Native Produce.
- An arrangement between New Zealand and China to engage more closely on environmental management issues, science and logistics around the Antarctic.
- An agreement to work more closely on climate change issues.
- A memorandum of understanding to help Chinese investment in New Zealand's forestry sector.