LONDON (Reuters) - The United Kingdom's Supreme Court said on Friday it would allow Scotland's most senior lawyer to address a December hearing on whether Prime Minister Theresa May needs parliamentary approval before triggering an exit from the European Union.

The British government is taking its case to the Supreme Court to appeal an earlier ruling by the High Court that parliamentary approval was required before the formal process of leaving the EU could begin.

The Supreme Court said Friday that it would allow the Lord Advocate of the Scottish government to address the relevance of Scots Law in the hearing. Legal representatives of the Welsh government, the Independent Workers Union and a group called the Expat Interveners will also be allowed to intervene.

Scotland's First Minister Nicola Sturgeon has said that triggering article 50 will "deprive Scotland of rights and freedom it currently enjoys".

(Reporting by Kate Holton; editing by Guy Faulconbridge)