LONDON — The British government was accused of bringing the country to the brink of a constitutional crisis Wednesday as Prime Minister Boris Johnson asked the queen to temporarily suspend Parliament.

Opponents see the move as an extraordinary attempt to make it harder for lawmakers to thwart the prime minister's Brexit plans before Oct. 31, the date the U.K. is scheduled to leave the European Union.

The prime minister confirmed in a letter that he had asked the queen to close Parliament from early September until mid-October. He said the current parliamentary session had gone on too long, and claimed the move was the best way to pursue his "bold and ambitious domestic legislative agenda."

The queen approved the prime minister's request during a meeting Wednesday at Balmoral Castle, the royal family's residence in Scotland. This was confirmed in a statement from the Privy Council, a group of royal advisers that includes government ministers.

"It would be a constitutional outrage if Parliament were prevented from holding the government to account at a time of national crisis. Profoundly undemocratic," tweeted Philip Hammond, the United Kingdom's former finance minister and a senior member of Johnson's own Conservative Party.

The speaker of the House of Commons, John Bercow, who was elected as a Conservative before taking up the impartial role, said such a move would be a "constitutional outrage."

Because the U.K. does not have a written constitution, some experts had asked if the queen could refuse the prime minister's request.

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On the opposition benches, Labour Party leader Jeremy Corbyn said in a statement that he was "appalled at the recklessness" of the move. "This is an outrage and a threat to our democracy," he added.

Labour lawmaker Ben Bradshaw said the decision was "a coup, plain and simple, against our parliamentary democracy." He warned it would "drag the monarch into an unprecedented constitutional crisis."

His colleague, David Lammy, called for people to "take to the streets in peaceful protest and civil disobedience" and called Johnson a "poundshop dictator" — using the British term for a dollar store.

Nicola Sturgeon, leader of the Scottish National Party, said that "today will go down in history as a dark one indeed for U.K. democracy."

The Institute for Government think tank said in a briefing paper in June that suspending Parliament in this way, officially known as "proroguing Parliament," would be "undemocratic" and "a deeply troubling precedent to set."

The news sent the pound down sharply, dropping to its lowest point in almost a week. Social media was dominated by trending topics such as "#stopthecoup." And an online petition calling for Johnson's action to be blocked had reached more than 200,000 digital signatures in just a few hours.

Why is this a big deal?

A showdown was already set for next week between the prime minister and the House of Commons, which is currently on recess. Johnson says that if he cannot negotiate a deal with the E.U. by the Oct. 31 deadline, he would be prepared to leave the bloc without a deal at all.

Many lawmakers from his own Conservative Party and all opposition parties want to stop this "no-deal Brexit" scenario at all costs. Some Conservatives have even threatened to bring down their own party in government by joining the Labour Party in a vote of no-confidence against their leader.

Others, such as former Conservative government minister and leadership candidate Rory Stewart, have threatened to set up their own rival legislature if Johnson suspends the House.

"Every other MP will sit across the road in Methodist Central Hall and we will hold our own session of Parliament," Stewart told Sky News in June. "We will bring him down."

They fear a "no-deal Brexit" scenario, which economists, business leaders and even the government's own leaked assessment have warned could trigger economic pain and even a shortage of food and medicine.

By suspending Parliament, Johnson is seeking to reduce the amount of time that lawmakers have to stop him before Oct. 31, according to his critics.

Johnson had refused to rule out the move for months, drawing condemnation from across the political spectrum. John Major, the former British prime minister of Johnson's own Conservative Party, likened him to Charles I, the king who prorogued Parliament and was beheaded in 1649.

"It didn't end well for him" and "shouldn't end well" for Johnson either, Major told the BBC in July.

What does proroguing Parliament mean?

Proroguing Parliament is not an unusual move. Parliament operates in cycles, starting with its opening and ending with its closing — or "proroguing."

Under the U.K.'s constitutional monarchy, the power to do this is formally given by the queen on the advice of the Privy Council.

The Commons Chamber in the Palace of Westminster, London. Universal Images / Getty file

Because it's usually procedural, the involvement of the apolitical queen is normally uncontroversial. Indeed, Daniel Hannan, a Conservative European lawmaker and one of the architects of Brexit, said that Johnson's move Wednesday was nothing outside the ordinary.

"A prorogation normally happens every autumn. This parliamentary session has lasted three years — the longest since the Civil War," he tweeted. "What kind of screwed-up mindset do you need to see the long-overdue return of constitutional normality as 'a coup'?"

In his letter, Johnson said that his decision was aimed at pushing through domestic policy, rather than a cynical strategic move. "We will help the NHS, fight violent crime, invest in infrastructure and science, and cut the cost of living," he wrote.

The NHS, or the National Health Service, is a huge and much-loved institution and its funding is a frequent subject of debate.

Some allege that Johnson is asking the queen to step in for what they say are shady political ends, and that puts the country in uncharted territory.

"Asking the queen to give effect to this strategy would draw her into a massive political debate," The Institute for Government said in its June briefing paper.

This is "something which Number 10 and the Palace are normally at great pains to avoid," the institute said referring to the official residences of the prime minister and the queen, respectively.