Harsh anti-gay laws in Uganda have been put on hold while the President seeks advice from scientists.
Yoweri Museveni wants to find out whether people are born gay and has commissioned American experts to find out.
His change of heart appears to be an attempt to protect the cash Uganda receives from countries like the UK and the United States.
The bill, which would extend the penalty of life imprisonment to "same-sex behaviour", has been condemned around the world and led to threats that aid could be withdrawn from the Uganda if it is passed.
Gay sex already results in life-imprisonment.
Uganda's president Yoweri Museveni was set to sign the bill into law
The bill was first introduced in 2009, with the death penalty as the sanction. This was scaled back to life in jail when the Parliament voted in through in December.
The bill was set to become law, but Museveni has stalled at the last minute.
"I therefore encourage the US government to help us by working with our scientists to study whether, indeed, there are people who are born homosexual," the Guardian reported him saying.
"When that is proved, we can review this legislation."
His announcement represents a u-turn from last week, when the president said he was ready to sign the bill into law because Ugandan scientists had determined that there was no "gene" for homosexuality, CNN reported.
"It was learned and could be unlearned", he said at the time.