UNITED NATIONS, Sept 1 (Reuters) - This week's fatal shooting of four Israelis in the West Bank was a transparent attempt to derail the first direct peace talks between the Israelis and Palestinians, the U.N. chief said on Wednesday.

This attack must be recognized for what it is -- a cynical and blatant attempt to undermine the direct Israeli-Palestinian negotiations starting tomorrow, U.N. Secretary-General Ban Ki-moon said in a statement issued by his press office.

Negotiations are the only way for the parties to resolve all final status issues, the statement said, adding that Ban urged both sides to show leadership, courage, and responsibility to realize the aspirations of both peoples.

Hamas Islamists in the Gaza Strip issued a statement claiming responsibility for the shooting attack on Tuesday that killed four Israelis in the occupied West Bank on the eve of peace talks in Washington.

The statement from the armed wing of Hamas, a group that opposes any dialogue with the Jewish state, said the Qassam Brigades announces its full responsibility for the heroic operation in Hebron. It also warned of further attacks. (Reporting by Louis Charbonneau; editing by Vicki Allen)