This week's <a href="https://www.thenationalnews.com/news/europe/2024/07/03/nato-pledges-40-billion-in-military-aid-for-ukraine/" target="_blank">Nato summit</a> in Washington is a crucial moment for US President <a href="https://www.thenationalnews.com/tags/joe-biden" target="_blank">Joe Biden </a>to tackle two distinct challenges: rallying international leaders in support of Ukraine and projecting confidence at home to his increasingly pessimistic <a href="https://www.thenationalnews.com/news/us/2024/07/03/nobody-is-pushing-me-out-biden-seeks-to-reassure-nervous-democrats/" target="_blank">Democratic Party</a> over his ability to triumph in November's election. The summit marking the alliance's 75th anniversary comes after Mr Biden's dismal <a href="https://www.thenationalnews.com/news/us/2024/06/27/presidential-debate-biden-trump/" target="_blank">debate performance </a>against his Republican rival <a href="https://www.thenationalnews.com/tags/donald-trump/" target="_blank">Donald Trump</a> last month. Normally, such an event would allow a US leader to showcase America's leadership on key global issues. Instead, Mr Biden will be working to convince colleagues and a sceptical public that he has the physical and mental wherewithal to remain in the White House. Following a 90-minute debate in which Mr Biden frequently failed to finish thoughts and sentences, the embattled 81-year-old President is defending against a growing corner of his own Democratic Party that is publicly calling for him to step aside and allow another candidate to take his place. In an apparent attempt to rebuff criticism that he is unable to adequately field questions from the press or speak without the aid of a teleprompter, Mr Biden on Monday phoned MSNBC and spoke live about his determination to continue his campaign. “I'm not going to explain any more about what I should or shouldn't do,” he said. “I am running. I am running.” On his foreign policy posture, he added: “I made sure that we're in a position where we have a coalition of people of nations around the world to deal with China, with Russia, with everything that's going on in the world, we're making real progress. “The Biden plan in Israel, for the Gaza Strip, it is something that was adopted by the UN Security Council.” During the Nato summit, Mr Biden will have a home-field advantage in promoting a vision of “western world order”, in contrast to the more obstructionist Trump, who has said he would encourage Russia to do “whatever the hell they want” to any Nato country that does not pay its dues. The 32-member alliance is planning to announce a series of measures to boost <a href="https://www.thenationalnews.com/news/us/2024/06/26/foreign-policy-looms-large-as-biden-and-trump-prepare-for-debate/" target="_blank">Ukraine's</a> defence capabilities, White House officials said. Mr Biden is scheduled to deliver remarks on Tuesday, according to the White House, and will participate in a variety of working sessions throughout the week that will also serve as a test of his sharpness post-debate. He is also due to give a press conference on Thursday – his first since the debate. But it may take much more to convince his Democratic critics. In a letter to Democratic members of Congress as they returned to Washington from a holiday break, Mr Biden wrote: “I am firmly committed to staying in this race … any weakening of resolve or lack of clarity about the task ahead only helps Trump and hurts us.” Congresswoman Annie Craig, who holds a vulnerable House seat in the Midwestern state of Minnesota, released a statement on Saturday calling on Mr Biden “to step aside as the Democratic nominee for a second term as President and allow for a new generation of leaders to step forward”. “This is not a decision I've come to lightly, but there is simply too much at stake to risk a second Donald Trump presidency,” Ms Craig added. She follows two other House Democrats to publicly call on the President to step aside last week, including Congressman Raul Grijalva, a progressive from Arizona, who told <i>The New York Times</i> that Mr Biden needs to “shoulder the responsibility for keeping that seat – and part of that responsibility is to get out of this race”. The amount of public calls to step aside from sitting Democratic officials remains restricted to those few legislators – but there are reports that the extent of defecting party members goes far beyond that, including senior figures involved in shaping foreign and military policy. Several US outlets reported on Sunday that four more House Democrats said during a leadership call that Mr Biden should drop his re-election bid, including House Armed Services Committee ranking member Adam Smith. Whether those Democrats will more publicly demand that Mr Biden step down as party front-runner as they return to Capitol Hill this week remains to be seen. Mr Smith will no doubt be watching closely as this week's Nato summit unfolds, as the leading Democrat on the armed services committee, which has oversight authority on the Department of Defence and the billions of support it has sent to Kyiv. <i>Punchbowl News</i> and <i>The Washington Post</i> reported that most on the Sunday call had advocated Vice President Kamala Harris leading the ticket with Mr Biden running as vice president. In a change from previous protocol, following the disastrous debate, Ms Harris has been joining Mr Biden for his daily national security briefs, according to White House schedules. Other Democrats in the House, including prominent Congressman James Clyburn, have previously said they would support Ms Harris leading the ticket alongside Mr Biden.