TEHRAN, Iran (AP) — Iran's top leader said Wednesday the United States is using "money and sexual attractions" to try to infiltrate the Islamic Republic and warned Iranians not to fall into the "enemy's trap."

Ayatollah Ali Khamenei told Revolutionary Guard commanders that authorities should take concerns about "infiltration" seriously and political factions should not use the issue against each other.

"The enemy sets up a network within a nation and inside a country mainly through the two means of money and sexual attractions to change ideals, beliefs and consequently the lifestyle," he said in comments posted on his website and broadcast on state TV.

His comments appeared to lend support to a recent wave of arrests of pro-Western writers and journalists, which hard-liners in the judiciary and security services have said is necessary to prevent Western infiltration.

Iran's moderate President Hassan Rouhani criticized the arrests earlier this month, saying hard-liners are "exaggerating the issue" and misusing Khamenei's warnings as an excuse for the detentions.

The recent arrests of pro-Western writers, journalists and filmmakers are widely seen as part of a backlash by hard-liners in the wake of the landmark nuclear agreement reached with the U.S. and five other world powers last summer. Hard-liners fear the deal could lead to a broader rapprochement between Tehran and Washington that would undermine and ultimately end the Islamic Republic.

Khamenei, who has the final say on all matters of state, said that "if some are making factional use of this (infiltration), it's a mistake. But these words should not lead to ignoring and forgetting the main issue of infiltration."