WASHINGTON — Prime Minister Benjamin Netanyahu landed in Washington on Sunday for what amounted to a brief campaign swing through the White House, hoping that President Trump’s praise and latest gift — recognition of Israeli sovereignty over the Golan Heights — would persuade wavering voters that his diplomatic achievements should offset any worries about his integrity.

Yet with barely two weeks left until Israel’s parliamentary elections, in which he is running neck and neck with Benny Gantz, a retired army chief, a fresh new scandal has embroiled Mr. Netanyahu, delaying his flight to Washington by hours and dogging him even after he arrived.

Mr. Netanyahu, who will also be leaving Washington earlier than expected after a rocket from Gaza struck a house in Israel, was already facing indictment on bribery and other corruption charges. He now faces two related accusations:

The first is that he improperly authorized the sale of advanced German-made submarines to Egypt without the approval of top military officials, possibly at a cost to Israel’s national security. The second is that he engaged in self-dealing, through an undisclosed and enormously profitable financial stake in a company that supplied the German builder of both the Egyptian subs and several new Israeli warships.

The new scandal builds on an earlier one involving the multibillion-dollar purchase of submarines and missile boats from the same Germany manufacturer.