The Palestine Liberation Organization issued a conciliatory reply today to King Hussein's Feb. 19 speech blaming it for a breakdown in Jordanian-PLO negotiations.

The statement, issued by PLO Chairman Yasser Arafat's office here, expressed "great regret" at the Jordanian monarch's speech, then went on to blame the rift on "Washington's continued bias in favor of the Zionist enemy."

The PLO said it still felt that there was a "distinctive relationship between the Jordanian and Palestinian peoples" and hoped "to transcend any negative developments" in its relationship with Jordan.

The statement was issued after a special meeting of the PLO Executive Committee in Tunis as the organization's formal response to Hussein's speech, in which he bitterly blamed the PLO for the breakdown, accused the organization of being untrustworthy and questioned the wisdom of the 1974 decision by Arab leaders to recognize the PLO as the only legitimate representative of the Palestinians.

"Instead of blaming the American stand for causing the failure of the Jordanian-PLO efforts, the PLO was held responsible," said the statement.

The PLO statement said Hussein was wrong in accusing the PLO of blocking progress toward peace by insisting that the United States guarantee the right of the Palestinians to "self-determination" in exchange for accepting U.N. Security Council resolutions recognizing Israel's right to exist within secure boundaries.

"The Palestinians' right to self- determination must be one of the bases upon which an international Middle East peace conference will convene so that that right will not be liable to rejection, cancellation or bargaining," the PLO statement said.