WASHINGTON — Senator Chuck Schumer (D-NY) implicitly accused US Secretary of State John Kerry of inadvertently aiding the boycott, divestment and sanctions movement, minutes before Kerry was expected to take the stage at the AIPAC Policy Conference’s Monday evening plenary.

Schumer was given a cold reception by the audience when he lauded President Barack Obama’s efforts on Iran, but the mood changed when he emerged, fists swinging, to confront the BDS movement – and his former colleague.

The senator criticized “friends” of Israel who pressured Israel to accept peace deals by warning them that if they didn’t, the movement against Israel would only strengthen. Such statements, Schumer argued, added to the strength of the BDS movement. Instead, Schumer said, “friends should be condemning the boycotts in every possible way, weakening them.”

Last month, Kerry warned that Israel was facing a growing delegitimization campaign that will increase should Israel fail to achieve peace in this round of talks.

“The risks are very high for Israel. People are talking about boycott,” Kerry said. “That will intensify in the case of failure,” Kerry said, and faced a firestorm of criticism by Israeli officials in response.

Schumer also said that the BDS movement fit in to a long historical pattern on unfair treatment of Jews that could only be described as “anti-Semitism.”

The criticism of Kerry’s BDS comments was not the only dig that Schumer took at the administration. He also qualified his support of the administration’s position on the P5+1 negotiations by stressing the importance of the passage of the Nuclear Weapons Free Iran Act, sanctions legislation which has divided Senate Democrats and which the administration vehemently opposes.

Schumer spoke minutes before Kerry was expected to deliver a keynote speech at the annual policy conference.

According to his prepared remarks, Kerry will address the BDS movement alongside Iran and the Israeli-Palestinian peace talks in his speech.

“In order for Israel to continue thriving economically, we must also stand together and with a single voice reject arbitrary and unwarranted boycotts of Israel,” Kerry’s speech reads. “For more than 30 years, I have staunchly, loudly and unapologetically opposed boycotts of Israel – and I will continue to staunchly, loudly and unapologetically oppose boycotts of Israel. That will never change.”

Kerry is expected to draw lines of comparison between different types of de-legitimization, and will promise that “every time Israel is subjected to attacks on its legitimacy, whether at the United Nations or from any nation, the United States will use every tool we have to defeat these efforts – and we will stand with Israel.”