LONDON (AP) — The British government was back at the country's Supreme Court on Wednesday, arguing that Prime Minister Boris Johnson's decision to suspend Parliament just weeks before the country is set to leave the European Union was neither improper nor illegal.

It's the second day of a historic three-day hearing that pits the powers of Britain's legislature against those of its executive as the country's scheduled Brexit date of Oct. 31 looms.

A government lawyer was set to argue that a lower court was right to rule that Johnson's suspension of Parliament was a matter of "high policy and politics," not law.

The government's opponents argue that Johnson illegally shut down Parliament just weeks before the country is due to leave the 28-nation bloc for the "improper purpose" of dodging lawmakers' scrutiny of his Brexit plans. They also accuse Johnson of misleading Queen Elizabeth II, whose formal approval was needed to suspend the legislature.

The government claims the shutdown was routine and not related to Brexit. And it says that, whatever the reason, under Britain's largely unwritten constitution, the suspension was a matter for politicians, not the courts.

Johnson sent lawmakers home on Sept. 9 until Oct. 14, which is barely two weeks before Britain's Oct. 31 departure from the EU.

The prime minister says Britain must leave the EU at the end of next month with or without a divorce deal. But many U.K. lawmakers believe a no-deal Brexit would be economically devastating and socially destabilizing. They have put obstacles in his way, including a law compelling the government to seek a delay to Brexit if it can't get a divorce deal with the EU.

Parliament's suspension spared Johnson further meddling by the House of Commons, but sparked legal challenges, to which lower courts gave contradictory rulings. England's High Court said the move was a political rather than legal matter but Scottish court judges ruled Johnson acted illegally "to avoid democratic scrutiny."

The Supreme Court is being asked to decide who was right.

A ruling against the government by the 11 Supreme Court judges could force Johnson to recall Parliament.

The justices are set to give their judgment sometime after the hearing ends on Thursday.

European Commission chief Jean-Claude Juncker, meanwhile, declared Wednesday that the risk of Britain leaving the EU without a divorce deal remains "very real" as EU lawmakers debated the ramifications of a no-deal Brexit. He spoke at the European Parliament in Strasbourg, France.

Juncker, who met with Johnson on Monday , said a no-deal Brexit "might be the choice of the U.K., but it will never be ours."

"I asked the British prime minister to specify the alternative arrangements that he could envisage," Juncker said. "As long as such proposals are not made, I cannot tell you — while looking you straight in the eye — that progress is being made."

After the debate, the European Parliament is set to adopt a resolution laying out its concerns about Britain's impending departure.

Samuel Petrequin in Brussels and Gregory Katz in London contributed to this story.

Follow AP's full coverage of Brexit and British politics at: https://www.apnews.com/Brexit