AMMAN, Jordan — Prime Minister Siniora of Lebanon will visit Iraq this week to discuss economic and bilateral ties, becoming the second Arab leader to visit the country since the American-led invasion in 2003.

The Lebanese premier will discuss ways in which Lebanon can benefit from “Iraq’s oil resources and how the two countries can boost trade and economic ties,” the prime minister’s spokesman, Aref al-Abed, said in a phone interview yesterday.

King Abdullah of Jordan visited Iraq last week, becoming the first Arab leader to do so since the invasion. The day after King Abdullah’s visit, Iraq, holder of the world’s third-largest oil reserves, agreed to sell oil to Jordan at a discounted price of $22 a barrel.

Jordan on June 30 named Nayef Zeidan ambassador to Iraq, where it had been represented by a lower-ranking charge d’affaires because of security concerns.

America has been pressuring the Sunni Muslim Gulf states and neighbors to cooperate in the development of the majority Shiite Muslim Iraq by canceling debts and opening diplomatic missions in the country.

President Bush, who leaves office in January, wants allies such as Saudi Arabia and Egypt to help strengthen Iraqi Prime Minister al-Maliki’s government at home and diminish interference from Iran and Syria.

Arab countries have expressed concern that Baghdad remains dangerous for diplomats and that Mr. Maliki favors his own dominant Shiite Muslim group over the country’s Sunnis and Kurds.