Joe Biden to address UN General Assembly for the last time as president

US President Joe Biden will look to burnish his foreign policy legacy in a UN speech on Tuesday, still facing the challenges posed by Ukraine's effort to repel Russian invaders and in a Middle East mired in war.

With four months left in office, Biden steps up to the green-marbled lectern to address world leaders at the UN General Assembly with wars in both regions posing dilemmas likely to outlast his presidency.

As efforts falter to impose a Gaza truce and with Israel and Lebanon's Hezbollah waging a cross-border battle, the Pentagon said on Monday it will send a small number of additional troops to the Middle East out of an abundance of caution.

Biden's presidency has been dominated by foreign policy challenges from Russia's February 2022 invasion of Ukraine to the Palestinian Hamas attack in southern Israel and hostage-taking last Oct. 7 and the resulting Israeli assault on Gaza.

Countering China and Iran, which backs both Hamas and Hezbollah, have consumed major chunks of the president's time.

A senior administration official said Biden's speech at 10 a.m. EDT (1400 GMT) will give him an opportunity to talk up what he considers major achievements of his time in office and to say the international community should support Ukraine and a diplomatic solution is needed in the Middle East.

White House press secretary Karine Jean-Pierre told reporters on the Air Force One flight to New York that Biden will outline his "vision for how the world should come together to resolve these big problems and defend fundamental principles such as the UN Charter."