TEL AVIV—Israel’s attorney general said he intends to charge Prime Minister Benjamin Netanyahu with bribery, fraud and breach of trust, imperiling Mr. Netanyahu’s bid to become the country’s longest-serving leader in an April election.

The charges are connected to three corruption probes and follow two years of investigations into the premier.

The allegations include charges that Mr. Netanyahu tried to influence media coverage of him and his family, along with accepting gifts from two billionaire businessmen in return for favors.

The move could mark an exceptional turn in a decadeslong career that has seen the premier at the center of Israel’s political right since the 1990s. It comes as his Likud party trails challengers from the center in polls, though he is projected to be in the best position to form a government.

The charges are pending a pretrial hearing that is likely to take place after the election. If they proceed and Mr. Netanyahu is re-elected, he could be the first sitting Israeli prime minister to face criminal charges. Israeli premiers aren’t required to resign if they are charged with a crime.