Romulo met with Annan during his official visit to the United Nations headquarters in New York last week.
"Secretary General Annan has accepted President Arroyos invitation. There is no definite date but it will be within the year," Romulo told a press briefing.
Ambassador Lauro Baja, the Philippines envoy to the UN, has set an appointment with him next week to discuss and finalize the arrangements.
Annan is expected to discuss with Mrs. Arroyo the Philippines role in world affairs, its economic recovery efforts as well as Manilas support for his efforts to reform the world body.
Annan expressed support for the governments reforms to revitalize the struggling economy as well as its efforts to forge a peace settlement with the separatist Moro Islamic Liberation Front during his meeting with Romulo.
"Mr. Annan gave his full support for our peace process and I briefed him on our progress. He expressed optimism and confidence in our success. I thanked him for his political support for our efforts to achieve peace," Romulo said.
Annan also agreed that international cooperation and adequate police powers for local authorities are crucial in thwarting regional terrorism.
He also expressed support for the Philippines initiatives to promote increased dialogue between religions in helping resolve world conflicts.
"I had a very frank and fruitful discussion with the secretary-general. He was upbeat and very supportive of our interfaith initiatives, including our plan to hold the Tripartite Conference for Interfaith Cooperation for Peace in June," he added.
Romulo also thanked Annan for sending a UN technical team to Manila to help the government draft an anti-terrorism law.
"We both agreed that internal legislation is important in this fight and I told him that after passing a major piece of reform legislation in the form of the VAT law, the legislative agenda of the President will now place our anti-terror bill on the front burner," he said.
The President invited Annan to visit the Philippines during a summit between Asian and African leaders in Jakarta in April. Mrs. Arroyo asked for Annans help in setting up an interfaith dialogue to be held under the auspices of the Philippines at the UN in September.
Annan asked for Manilas support for reforms he is planning to introduce in the UN, particularly to replace the bodys human rights commission with a more effective panel.
The commission has failed to do its job and puts the UNs credibility in question, he said.