Britain's high food and farming standards must be upheld as deepening trade relations with Mexico and Canada get underway, the NFU has said.
The union has submitted evidence to the Department for International Trade (DIT) consultations on potential UK trade agreements with the two countries.
Existing trade agreements between the EU and Canada and Mexico were ‘rolled over’ for the UK to ensure trade could continue post-Brexit.
The consultations looked at these existing free-trade agreements, as well as opportunities to improve trade in future negotiations.
The NFU highlighted existing barriers to trade, such as difficulty accessing the Canadian dairy market, particularly due to challenges around the quota system.
There is also greater opportunity for the UK to access the premium Canadian sugar market, as well as grow exports of poultry meat and eggs.
However, the union raised concerns about the risk of further liberalisation of the market for cereals, beef, pork and horticultural goods from Canada.
For Mexico, the NFU highlighted the lack of sufficient Export Health Certificates (EHCs) for pig meat, including fifth-quarter cuts. It called for greater access for these products into this market.
The NFU has also called for greater market access opportunities for British dairy, fruit and vegetables, poultry meat and organic goods into Mexico.
But the union highlighted concern about the potential for greater market access being given to Mexican exports of beef, eggs, sugar and horticultural goods into the UK.
"Across both trade deals there are other areas of opportunity including greater protection for Protected Geographic Indicators," the NFU added.
"We would also urge the UK government to take the opportunity these negotiations offer in developing ambitious policy to uphold standards such an animal welfare, SPS and environmental provisions, along with access to professional qualifications, across both sets of talks."
Negotiations for each country are expected to launch later this year.
It comes as Mexico officially opens its doors to British pork for the first time, in a deal that could be worth £50m over the first five years of trade.
Global UK pork exports were worth over £421 million to the economy in 2020, reaching 75 export markets worldwide.
According to the AHDB, access to the Mexican market alone is estimated to be worth £50m to UK pork producers over the first five years of trade.
Defra Secretary of State George Eustice said it was 'great' to see another market open its doors to 'high quality, high welfare UK produce'.
“Access to the Mexican market, with its substantial demand for high-quality pork, will be a welcome boost for our pig farmers and producers.
“This is a significant development, which will reinforce our global reputation for quality food and drink."