BAGHDAD — Iraq’s prime minister warned yesterday that foreign intelligence agencies are plotting to depose his government and install a former Baathist as leader.

Prime Minister al-Maliki said the effort of Ayad Allawi, the former prime minister, to build support for an alternative governing coalition was a front for the Egyptian, Saudi Arabian, and Turkish intelligence services.

Diplomats said last week that Mr. Maliki had briefly appeared to be “getting over his paranoia” about Mr. Allawi, one of the many factors that has paralyzed the Baghdad government.

But in his strongest denunciation yet of his rival’s high-profile efforts to oust the government, Mr. Maliki called on the army to take a stand against foreign interference.

In a speech to divisional commanders, he said, “I feel astonished when I hear some politicians, under the shadow of democracy, saying that there is nothing wrong with Arab and Islamic countries interfering in Iraq’s affairs.”

The Baathist Mr. Allawi, who once nearly died in an attack by Saddam Hussein’s agents after he defected, was Iraq’s first post-war prime minister.

His proposed National Front would bring his centrist secular MPs into an alliance with Sunni Muslim parties and disaffected elements of the Shiite and Kurdish political establishment.

Mr. Allawi has the strong backing of the Saudi Arabian government, which has signaled its lack of faith in Mr. Maliki. Last month, King Abdullah told Vice President Cheney that he would no longer work with Mr. Maliki.

Later, during a visit to Baghdad, Mr. Cheney told Iraqi officials that Washington’s support was not indefinite.