OTTAWA - Prime Minister Stephen Harper spoke with Benjamin Netanyahu today about the Israeli leader's visit to Washington and the prospects for Middle East peace negotiations.

A Harper spokesman said Canada will continue to encourage a two-state solution with all the parties involved in the peace process -- a concept a Netanyahu aide called "childish and stupid."

The aide spoke to reporters on the plane carrying Netanyahu home from talks in Washington -- which did not go well.

During his visit to the U.S. capital, Netanyahu avoided committing to the idea of a Palestinian state.

Instead, he said the key to solving the Israeli-Palestinian conflict is to halt Iran's nuclear program.

U.S. President Barack Obama made it clear Washington backs the creation of a Palestinian state.

The Netanyahu aide said the two-states-for-two-peoples idea is "childish and stupid, because the problem is more complex than that."

Harper and Netanyahu agreed to remain in close contact in the weeks ahead, a Harper spokesman said.

Meanwhile, a key Palestinian official demanded that Obama follow up his tough talk and force Israel to stop West Bank settlement construction and accept creation of a Palestinian state.

Palestinian negotiator Saeb Erekat warned that without action to reinforce Obama's words, the whole region could deteriorate into extremism and instability.