In November 2016, the high court in the UK ruled that British prime minister Theresa May does not have the authority to trigger Article 50 to begin Brexit negotiations without consulting parliament.

The government appealed this decision to the country's supreme court, but the appeal was dismissed on Tuesday this week. By a margin of eight to three, the 11 justices upheld November's High Court ruling.

There are some MPs who want the process to be delayed

This means that parliament must sanction the triggering of Article 50, which sets negotiations on Brexit into motion, before it goes ahead.

What happens next?

The BBC reports that both the House of Commons and House of Lords will have to vote in favour of it. It says the bill could pass through the Commons before the half-term recess in the middle of February, giving plenty of time for the Lords to consider it and for it to become law before the end of March - Theresa May's deadline for triggering Article 50.

It adds that while there are some MPs who want the process to be delayed, these are vastly outnumbered by those who want the government to get on with it so that the UK can trigger Article 50 by the end of March 2017 and be out of the EU by 2020, as planned.

Impact on agriculture

Ireland's agriculture sector is widely acknowledged to be the biggest future victim of the UK's departure from the EU. Over 40% of our food and drink exports go the UK every year.

Earlier this month, Theresa May outlined that she would be negotiating for a hard Brexit, although she said she would follow this up with the pursuit of an ambitious free-trade agreement with the EU.

Subsequent to this, markets specialist Phelim O'Neill took a look at how a hard Brexit would impact on Irish agriculture .

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