An ex-U.S. diplomat who admitted having sex with teenage girls and taping the encounters while stationed in Brazil and the Congo has been sentenced to 20 years in prison.

Gons Nachman had sought leniency, claiming cultural differences in those countries made sex with teenage girls more acceptable.

But a judge gave the 42-year-old the maximum sentence and took the unusual step of ordering consecutive 10-year terms for the two counts on which he was convicted.

Nachman pleaded guilty earlier this year to possessing child pornography after admitting he videotaped his sexual encounters while working as a consular officer. The case also included allegations that he pressured Brazilian visa applicants for sex, though he was not charged with that.