Photo credit: APUS President Donald Trump expects all Nato allies attending next week's summit in Ankara to be on a path toward spending 5 per cent of Gross Domestic Product (GDP) on defence and related measures, US ambassador to Nato Matthew Whitaker said on Wednesday.Speaking to news agency Reuters, ahead of the July 7-8 summit, Whitaker said some allies were contributing more than others and that those making greater contributions should receive corresponding benefits.Whitaker said some Nato members were not spending enough on defence or lacked a credible plan to meet the proposed target, expressing US President Donald Trump’s disappointment towards Spain."We have some that are lagging behind that either are not spending enough right now or don't have a credible path. President Trump fully expects that all allies will step up immediately and get on the path to 5 per cent," he said.He added that the United States and its allies were working together to support Ukraine and that Washington expected European allies to shoulder a greater share of that effort."We are working together to support Ukraine. We expect our European allies to bear the burden," he said.According to Reuters, Whitaker said announcements by the United States and its allies on support for Ukraine would be substantial and long-term, sustained commitments to Ukraine should be expected at the Ankara summit.The ambassador also said Nato should prioritise strengthening defence industrial capacity."We need to most importantly focus on the defence industry and defence industrial capacity," he said.He criticised protectionist language in European defence initiatives and added that there was not enough consolidation in the European defence industry.Despite the differences with its allies, Whitaker said he expected the meeting to be successful."I think we're prepared to have a very successful summit," he said.