There is no evidence that the Israeli government has issued an announcement that it will 'begin its ethnic cleansing' of any city, nor does the claim identify a specific city that Israel has physically destroyed.
UK accuses Israeli ‘terrorists’ of ethnic cleansing in West Bank with government...Primary Source Extraction
"Heading: UK accuses Israeli ‘terrorists’ of ethnic cleansing in West Bank with government backing In response, the Israeli foreign minister, Gideon Saar, announced the closure of the UK consulate in Jerusalem and that 12 British MPs and activists – including Jeremy Corbyn and Labour MP Diane Abbott – would be banned from entering Israel. Saar accused Miliband of “outrageous lies” and said the UK government was “systematically working against the state of Israel”. Washington’s ambassador to Israel, Mike Huckabee, warned that the US could take retaliatory action over trade."
