……….IS THE UK PARLIAMENT STILL SOVEREIGN?
IF NOT, WHO IS?

The underlying organising principle of the UK constitutional system has been that Parliament, not the monarch, and not people by referendum, is sovereign.
This principle may not be contained in a written constitution, but it is longstanding.
It was established in the seventeenth century by the outcome of the Civil War 1646/9, where Parliament defeated the monarch (Charles I) and his ministers, and by the Revolution of 1688 whereby Parliament deposed the legitimate monarch (James II).
In contrast, in Ireland, the Houses of the Oireachtas are not sovereign, in the sense that, since 1937, it is only the people who, by referendum, can change the Irish constitution.
The developing clash this week between the government of the UK (the Queen’s Ministers to use 17th century terms) and the majority in Parliament, over the latter’s rejection of the Brexit Withdrawal Agreement, is creating a crisis in the UK constitution.
This crisis is derived from the fact that the UK government intentionally ran down the clock and delayed voting on the Withdrawal
It is arguable that this level of pressure on Parliament by the executive is contrary to the UK constitution.The government of the UK should, in accordance with tradition, act as a servant of Parliament, not the other way around.
But, instead, the government is demanding that Parliament vote, over and over again, on the same question, citing the idea that it would be undemocratic to have a second Referendum on Brexit, and claiming that to respect the referendum result, PM May’s Withdrawal Agreement must be voted through by Parliament.
If Parliament is to be asked to change its mind, there is no logical reason for the people, in a referendum, should not also be allowed to do the same.
The UK may also need to revise its unwritten constitution, to define more clearly the respective roles of government and Parliament, in regard to international negotiations