Rishi Sunak has demonstrated a “little England mentality” in foreign relations, David Lammy has argued, warning the UK risks marginalising itself in vital global debates on China, AI and the climate emergency. Speaking shortly before Sunak heads to Washington for a meeting with Joe Biden, the shadow foreign secretary said cuts to areas such as overseas aid, the British Council and BBC World Service were further hampering the UK’s soft power and making it appear even more insular. “Sunak finds himself constantly on the fringe of the debates and never leading, never at the centre,” Lammy told the Guardian from a defence and security conference in Singapore. “I think that there are two traditions, effectively, in our country. One is a Great Britain that’s outward-looking and open. The other is a little England. We’ve seen a lot of the little England mentality under this government.” The Tottenham MP, who has held the foreign affairs brief under Keir Starmer for the past 18 months, has previously set out his hope to better reconnect the UK with other nations if Labour wins power. Such an approach, Lammy argued, also includes China, whose new defence minister, Li Shangfu, spoke at the Singapore gathering, as did Li’s US’s equivalent, Lloyd Austin. As well as challenging Beijing, notably over rights abuses in places including Hong Kong and Xinjiang, Lammy said the UK had to accept the necessity of cooperation, notably over climate issues. The Conservatives, he said, had shown “massive inconsistency” over China, ranging from the self-styled “golden era” of relations under David Cameron to the hostility of Liz Truss, who made a speech last month in Taiwan, which is threatened by potential invasion by China. Truss’s intervention could have been harmful if people saw her as a more consequential figure, Lammy argued: “I don’t think any serious commentator that I’ve seen thought it was a sensible thing for a former UK prime minister to arrive in Taiwan sabre-rattling. But I didn’t see write-ups of that speech taking it very seriously.” All this epitomised a chaotic embrace of foreign relations under Sunak and his predecessors, Lammy said, which had managed to alienate allies such as the EU and the US. “We had this incomprehensible approach to Northern Ireland, the UK government apparently prepared to tear up an international agreement we had signed up to just two years previously. That undermined our relationship with Washington,” he said. “We’ve had a very sclerotic approach to climate, vastly different to the Biden administration, with their inflation reduction act. “All of this has put Britain on the fringe. It’s on the fringe of Europe, not at the centre of discussions on artificial intelligence, on climate, on defence cooperation beyond the Nato framework.” One immediate task for a Labour government if it wins an election expected next year would be to begin negotiations on a revised post-Brexit trading deal, with Lammy saying he would hope to improve ties in areas including the movement of food, and getting EU students back into UK universities. While Lammy and his party have close ties with Biden’s team, they also face the prospect of a near-parallel US election cycle delivering a Republican president – potentially even Donald Trump – into the White House. “While I spend time with good Democrat friends who are currently in the administration, and on the Hill, it’s also important to meet with Republicans and talk to Republicans and understand their worldview,” said Lammy, who previously studied and worked in the US. “That relationship goes beyond whomever is in No 10 or the White House.” While Labour has said it will restore the UK’s aid budget to 0.7% of GDP only if economically possible, Lammy argued this was a vital element of a more connected foreign policy. “Our soft power is also the BBC World Service. It’s the British Council. It’s higher education and getting back into the [EU’s] Horizon scheme. “Of course, I want to see us get back to the global outside reputation that we had on international development, as soon as the fiscal climate will allow.” This was, he said, another example of the foreign policy slippage under Sunak: “Our economy is weaker, our soft power is less. And our relationship with our allies is not as strong as you would expect it to be, given that there is war in Europe. So on all of those fronts, there is a lot for the next government to do.”