<p>US President Joe Biden told new Prime Minister Rishi Sunak -- Britain's third leader in two months -- that "the UK remains America's closest ally", in a phone call on Tuesday, Downing Street said.</p>.<p>"The leaders discussed the extent of UK-US cooperation, both bilaterally and in regions such as the Indo-Pacific," Sunak's office said, while noting they also discussed the more contentious issue of Northern Ireland.</p>.<p>The trans-Atlantic allies will meet in person at a G20 Summit in Indonesia next month.</p>
<p>US President Joe Biden told new Prime Minister Rishi Sunak -- Britain's third leader in two months -- that "the UK remains America's closest ally", in a phone call on Tuesday, Downing Street said.</p>.<p>"The leaders discussed the extent of UK-US cooperation, both bilaterally and in regions such as the Indo-Pacific," Sunak's office said, while noting they also discussed the more contentious issue of Northern Ireland.</p>.<p>The trans-Atlantic allies will meet in person at a G20 Summit in Indonesia next month.</p>