Major League Baseball has sent a warning to teams about encouraging players subject to the MLB draft to withdraw from high school baseball to become eligible to sign as international players.

An MLB spokesman declined comment.

The key section of the memo sent to teams Monday and obtained by ESPN reads: "It has come to our attention that Clubs have been encouraging amateur players in the United States to withdraw from, or otherwise refrain from playing, high school baseball in the United States and/or Canada, in order to try to establish residency in a foreign country, in an effort to make themselves eligible to sign under the International Amateur Talent System instead of the Rule 4 Draft."

In the memo, the league clarified the rules around eligibility and what rules teams were breaking by encouraging players to change their eligibility. The memo says that encouraging players to make this change "shall be subject to significant penalties, including, but not limited to, the denial of player selection rights under the [MLB draft] or loss of benefits under the International Amateur Talent System."