The two candidates vying to be Britain’s next prime minister will face off in a TV debate Monday, after both sought to woo the Conservative Party’s right-wing base by backing a controversial plan to deport some asylum-seekers to Rwanda. Foreign Secretary Liz Truss and former Treasury chief Rishi Sunak are battling to succeed the discredited Boris Johnson as head of Britain’s governing party. They were chosen by Conservative lawmakers from an initial field of 11 candidates as finalists to replace Johnson, who quit as party leader on July 7 after months of ethics scandals triggered a mass exodus of ministers from his government. The winner will automatically become prime minister, governing a country of 67 million — but will be chosen by about 180,000 Conservative Party members. They will vote over the summer with the result announced Sept. 5. Johnson remains caretaker prime minister until his successor is chosen. Also read: Britain’s Boris Johnson battles to stay as PM amid revolt Truss, 46, and 42-year-old Sunak have wooed Conservatives by doubling down on policies thought to appeal to the Tory grassroots. Both are backing a contentious deal agreed by the Johnson government with Rwanda to send some migrants who arrive in Britain in small boats on a one-way trip to the East African nation. The deportees would be allowed to apply for asylum in Rwanda, not the U.K. The government says the policy will deter people-traffickers from sending migrants on hazardous journeys across the Channel. Political opponents, human rights organizations and even a few Conservative lawmakers say it is immoral, illegal and a waste of taxpayers’ money. The first scheduled deportation flight was grounded after legal rulings last month, and the whole policy is now being challenged in the British courts. Also read: Sunak, Truss emerge as finalists in UK leadership race On Sunday, Sunak said “no options should be off the table” despite questions over the policy’s legality and morality. Truss said she was “determined” to see the Rwanda plan through and raised the possibility of expanding it to additional countries. Truss also said she would expand the size of the U.K. Border Force, while Sunak has suggested housing asylum-seekers on cruise ships. Hard-line policies like the Rwanda plan are less popular with voters as a whole than with Conservatives, but the British electorate won’t get a say on the government until the next national election, due by the end of 2024. Truss and Sunak have already clashed over economic policy, with Truss promising immediate tax cuts and Sunak — who shepherded Britain’s economy through the coronavirus pandemic — saying he will get inflation under control before slashing taxes. He says borrowing more to cut taxes would be “immoral.” The leadership election is taking place during a cost-of-living crisis driven by soaring food and energy prices, partly due to the war in Ukraine. While many countries are experiencing economic turbulence, in Britain it’s compounded by the country’s departure from the European Union, which has complicated travel and business relations with the U.K.’s biggest trading partner. Both Sunak and Truss are strong supporters of Brexit, which was the signature policy of the Johnson government. But the two have sparred on topics such as policy toward China, with allies of Truss accusing Sunak of changing his stance on relations with Beijing. Sunak says China represents the “biggest-long term threat to Britain,” and says that if elected he would close the 30 Confucius Institutes in Britain. Funded by the Chinese government, the institutes teach Chinese language and culture, but have been accused of spreading pro-Beijing propaganda. Former Conservative leader Iain Duncan Smith, a longtime China critic who backs Truss, said Sunak’s Treasury had previously “pushed hard for an economic deal with China.” “Where have you been over the last two years?” he said.