Organisation said it would challenge in the British courts "any improper attempt to restrict its activity"
The Muslim Brotherhood has urged Britain not to bow to foreign pressure in conducting a review of the group over concerns about possible links to violence, following its designation by Egypt and Saudi Arabia as a terrorist organisation.
In a statement, the movement said that it would "openly engage" with the review ordered by Prime Minister David Cameron but it would challenge in the British courts "any improper attempt to restrict its activity".
The Brotherhood, a movement whose affiliated groups have deep roots in many Arab and Islamic states, said it was concerned that Britain's ambassador to Saudi Arabia, John Jenkins, would be leading the review, the statement issued late on Wednesday said.
Saudi Arabia, a commercial ally of Britain and staunch foe of the Brotherhood, designated the group a terrorist organisation last month following a similar move by Egypt in December.
"It is important that the British government does not bend to pressure from foreign governments who are concerned about their own people's quest for democracy," the statement released by the Brotherhood's press office in London said.
"It is hard to see how Sir John Jenkins will be able to conduct an independent internal review of the Muslim Brotherhood and carry his brief as Ambassador to a non-democratic regime that is openly in political opposition to the Muslim Brotherhood."
Riyadh has given the Egyptian army, which deposed Islamist President Mohamed Mursi last year after mass protests against his rule, billions of dollars to support the beleaguered economy.
When asked why Jenkins was leading the review, a spokeswoman for Cameron said on Tuesday it was because it would focus on the group across the region, not just Egypt, and Jenkins had deep knowledge of the Middle East.
The Brotherhood gained political power in some Arab nations after the 2011 uprisings that toppled autocratic rulers. But the group has since been crushed in Egypt after the military overthrew Mursi in July and been subjected to a wave of prosecutions and jailings in Gulf Arab kingdoms leery of any spread of Islamist influence since the Arab Spring uprisings.
Britain, where many Brotherhood-influenced organisations are based, said its review would include looking at allegations made by Arab leaders that the group was linked to violence, a charge it has repeatedly denied.
Britain's move follows increasing Arab repression of the Brotherhood especially in Egypt, where security forces have killed hundreds of Islamists and jailed thousands including almost all leaders of the movement since the army ousted Mursi.
The Brotherhood asked the review to consider what it said were "serious human rights abuses being conducted by the military regime in Egypt".
"The British government should be cautious not to allow this review to be seen as an endorsement of the criminal acts which continue to be perpetrated against the people of Egypt."
The Egyptian government denies allegations of human rights violations.