In today’s newsletter: James Cleverly has signed a treaty aimed at fixing its deportation plan, but there are questions whether its safeguards will change the supreme court’s mind

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Good morning. Whoever it was that bequeathed the Conservative government its current dog’s dinner of a policy on immigration and asylum, be in no doubt: the people in charge now are going to do things differently! After setting out draconian new limits on legal migration on Monday, home secretary James Cleverly yesterday turned to irregular migration and the small boats crisis.

In Kigali, he signed a new treaty with the Rwandan government that is supposed to help overcome the supreme court’s recent decision that the existing Rwanda deportation plans are unlawful. Next, the government will proceed with the second part of its plan to fix the Rwanda scheme: legislation that could prevent new court challenges. As he finalises plans that could be published tomorrow, Rishi Sunak must decide whether he wants to infuriate his party’s moderate MPs or those rallying around Suella Braverman on the right.

Israel-Hamas war | The UN’s top aid official has said the Israeli military campaign in southern Gaza has been just as devastating as in the north, creating “apocalyptic” conditions and ending any possibility of meaningful humanitarian operations. Meanwhile, the UN heard accounts of sexual violence during the 7 October attacks by Hamas in a meeting where speakers accused women’s rights activists and UN officials of not doing enough to address the crimes.

Climate | Many of the gravest threats to humanity are drawing closer, as carbon pollution heats the planet to ever more dangerous levels, scientists have warned. Five important natural thresholds already risk being crossed, according to the Global Tipping Points report, and three more may be reached in the 2030s if the world heats 1.5C above pre-industrial temperatures.

Nuclear leaks | Sellafield, Europe’s most hazardous nuclear site, has a worsening leak from a huge silo of radioactive waste that could pose a risk to the public, the Guardian revealed. Concerns over safety at the crumbling building have caused diplomatic tensions with countries including the US, Norway and Ireland.

Covid inquiry | The mystery of Boris Johnson’s Covid-era WhatsApp messages has taken another twist before the former prime minister begins his evidence to the inquiry today, after it was reported that nearly six months of messages could not be retrieved. A spokesperson for Johnson blamed a “technical issue”.

NHS | Thousands of junior doctors are to stage new strike action in England after failing to reach a deal with the government in talks over pay. They will walk out for 72 hours from 7am on 20 December, and again for six days from 3 January.