Spain's deputy prime minister called on Ibero-American countries Monday to make legal security a pillar of their institutional framework in order to create a "stable, favorable environment for business."

Soraya Saenz de Santamaria made that her keynote message to a meeting in Madrid of officials from 21 nations who are preparing for November's Ibero-American Summit in the southern Spanish city of Cadiz.

The meeting is being held amid controversy that erupted with Argentina's expropriation of YPF, a unit of Spanish oil major Repsol, and Bolivia's nationalization of a subsidiary of Spanish utility REE.

Without addressing the two cases specifically, Saenz de Santamaria used the occasion to make a strong defense of the principle of security under the law and respect for foreign investment.

"If we can agree on that fundamental point, on the importance of creating confidence and predictability, then we should avoid actions that work against that indispensable economic and social value," she said.

Legal security is key to Latin America being known a region that is "open to the world and worthy of trust," the deputy premier said.

"This principle should be strengthened to avoid giving the international community even the shadow of a doubt," she said.

Joining Saenz de Santamaria for Monday's event was Spain's secretary of state for Ibero-America, Jesus Gracia, who will travel this week to Bolivia to tackle the case of the REE affiliate.

The Madrid meeting, whose theme is "Institutional strengthening for economic growth and social unity" is being attended by representatives of 21 countries.

Argentina is keeping a low profile and its delegation is headed by the minister-counselor of his embassy in Madrid, Maria Belen Bogado, while Bolivia sent Education Minister Roberto Aguilar.

Saenz de Santamaria told guests of her wish that the Cadiz Summit will give a "new and enthusiastic boost" to relations among Ibero-American countries, coinciding with the 200th anniversary of Spain's 1812 constitution.

"Spain has the best will in the world. We're determined to build a new relationship among all our countries that forgets the stereotypes of the past and overcomes the obstacles still present," she said.

Prime Minister Mariano Rajoy's government hopes to maintain relations of "absolute equality and mutual respect for the democratic processes of every nation," Saenz de Santamaria said.