The correct answer to this open question is the following.
It was Oliver North who masterminded the plan to use the proceeds of the “arms for hostages” deal to fund the Nicaraguan rebels in what became known as the Iran–Contra scandal.
The plan was a secret one and including the selling of weapons and missiles to Lebanon in order to free American hostages. The funds from the weapons were used to support the Contras in Nicaragua. United President Ronald Reagan instructed Robert McFarland -National Security Advisor- to support the Contras in the armed conflict in Nicaragua.