Central American nations reached an agreement on Monday to allow several thousand Cuban migrants who have been stranded in Costa Rica to continue on to the United States. An estimated 250 migrants will initially be transported from Costa Rica to El Salvador and put on buses to take them toward Mexico during the first week of January, Costa Rica's Foreign Ministry said in a statement. Costa Rica halted its issuing of transit visas for Cuban migrants on Dec. 18, citing that the country had exhausted local resources in providing shelter. Cuban migrants receive preferential asylum under American policy and can apply for residency if they reach the border by land. The number of Cuban migrants has surged in recent months over fears that the preferential treatment would end as Washington and Havana continue to renew relations.