...We assign long-term and short-term senior unsecured debt and issuer ratings of A3 and Prime-2, respectively, to Nacional Financiera, S.N.C., Instituci=n de Banca de Desarrollo (Nafin), with a stable outlook, and Aaa.mx/MX-1 Mexican national scale issuer ratings. Nafin's ratings take into account our assumptions of a very high likelihood of support from the Government of Mexico (A3 stable) and a standalone Baseline Credit Assessment (BCA) of ba1 based on the bank's relatively low risk profile, underscored by its main focus on second- floor financing, with exposures mainly to banks and other types of financial institutions rather than direct financing to the ultimate borrowers. The BCA is also underpinned by Nafin's ample level of high-quality capital. Nafin's standalone strength is constrained by its high reliance on market funding, which increases re-pricing risks as interest rates continue to rise. The BCA is also constrained by the bank's limited business scope because it caters mainly...