The President described Jammehs visit as "God-sent" as he also vowed to back the Philippines bid for "permanent" observer status in the influential Organization of Islamic Conference (OIC).
During the state lunch Mrs. Arroyo hosted for Jammeh, she said the Gambian leader informed her that his country had struck oil and that it would be willing to share its find with Manila which she called a "wonderful piece of good news."
At the same time, the President sought the support of Gambia as an important member of the OIC.
"Your support is valuable in our efforts to forge lasting peace with our Muslim brothers in southern Philippines. With your support, the Philippines looks forward to a future of being one among you in the OIC," she said.
Mrs. Arroyo thanked Jammeh for Gambias commitment to fully supporting the Philippines bid for "permanent observer" in the OIC.
"We are committed to promoting understanding among various faiths and civilization in our country and in the world," the President said.
She also welcomed Jammehs news about oil discovery in Gambia, saying it "bolsters my own faith that God the Father or Allah as he is called in the Muslim world has perfect timing."
"Yesterday, we were appalled to read about the unprecedented rise in the price of oil to 59 dollars per barrel. And I started my conversation with His Excellency, talking about how important it is for us to address that issue because we are poor countries heavily dependent on imported oil," she said.
"And His Excellency, the President, gave me a wonderful piece of good news. Gambia has just discovered oil. And because the Philippines helped out Gambia in its earlier days struggling as a nation, Gambia will help us out this time by giving a bloc for the oil exploration of our Philippine Oil Exploration Company," Mrs. Arroyo said.
Mrs. Arroyo noted the increase in world crude prices was unprecedented and that both countries were looking for ways to mitigate its impact.
Jammeh is the first African leader to visit the Philippines during Mrs. Arroyos term.
"As developing nations, we can support each other through cooperative efforts and with the assistance of common friends and allies through various tripartite or multilateral arrangements as we endeavor to produce ways and means to improve the lives of our people," the President said.
"And I am very happy that His Excellency President Jammeh said that they are our friends forever because of what we have done for them in the early days of the development of their new independent nation," she added.
The President said as acknowledgment of the Philippines help to Gambia since their independence in 1965, a variety of peanuts their main export product was called "Philippine pink."
"It is also called brokos because it was brought there by a professor Brookes from the Philippines and 70 percent of their experts have studied in the Philippines headed by no less than their incumbent vice president who studied (here)," she said.
Mrs. Arroyo invited the Gambian leader to visit during the Asian African Summit in Jakarta, Indonesia last April, where the Philippine president warned that the continuous increase in oil prices could halt economic growth and lead to global recession.
She said developing countries would be hardest hit and that they should work together to cope with the rise in crude prices, which result in high transportation fares and prices of basic commodities.
Mrs. Arroyo and Jammeh also witnessed the signing ceremony of agreements at Malacañangs Reception Hall right after their bilateral meeting.
The Gambian leader arrived early Monday night and leaves on June 23.
Jammeh will also tour the Technical Education and Skills Development Authority, Center for International Trade Exhibitions and Missions, World Trade Center, Bureau of Fisheries and Aquatic Resources, Private Residential Rehabilitative Institutions and the Department of Healths research and training facilities.