In an article on FaithFreedom.org, Jennifer King claims:
Ayatollah Ruhollah Khomeini, The Supreme Leader of Iran, the Shia Grand Ayatollah, 1979-89 said in his official statements:
"A man can quench his sexual lusts with a child as young as a baby. However, he should not penetrate. Sodomizing the baby is halal (allowed by sharia). If the man penetrates and damages the child, then he should be responsible for her subsistence all her life. This girl, however, does not count as one of his four permanent wives. The man will not be eligible to marry the girl’s sister. It is better for a girl to marry when her menstruation starts, and at her husband's house rather than her father's home. Any father marrying his daughter so young will have a permanent place in heaven."
The same claim was published in this book written by Nonie Darwish (author of Gatestone Institute) and this book written by Gareth Wilson. And the first four lines of the quote are mentioned in this link.