US President Joe Biden remains “convinced” of a successful outcome to negotiations in Washington on raising the US debt ceiling, which requires congressional approval, White House spokeswoman Karin Jean-Pierre said today.

There are still “substantial differences” between Democrats and Republicans, but “we are optimistic,” Jean-Pierre told reporters in Hiroshima, where the US president is for the G7 summit.

If no deal is reached in Congress to raise the US debt ceiling by June 1, the world’s largest economy could face the unprecedented scenario of declaring a default.

Republican Rep. Patrick McHenry cast doubt on whether a deal could be reached over the weekend after another fruitless meeting on Friday night.