The closer the dovish Israel lobby J Street gets to its first national conference, the louder the controversy surrounding its activity grows.

J Street, committed to being “pro-Israel and pro-peace”, has been under fire since it took its first steps 18 months ago. But as it reaches a major milestone — a grand conference scheduled for next week and fashioned after the similar annual event held by the more established, mainstream Israel lobby, Aipac — criticism is mounting from all fronts: the Israeli government, hawkish Jewish activists, and members of Congress.

The hurdle facing J Street is to prove to the Jewish community that its views, calling for strong US push for a two-state solution and an end to Israeli settlement activity, are not that far from the mainstream of the Jewish community and do not contradict Israeli interests.

But two weeks before its conference, J Street was slapped with a harsh statement from the Israeli embassy in Washington, claiming that the embassy has “concern over certain policies that could impair Israel’s interests”.

To make the point even clearer, the Israeli ambassador to Washington, Michael Oren, refused to meet with members of the group and, after refusing to reply to an open invitation to speak at the conference, finally declined it this week.

In an open letter to the ambassador before he replied, Jeremy Ben-Ami, J Street’s executive director, said the forum should be used for mutually convincing each other and to “argue over how best to ensure the health, safety and vibrancy of the Jewish people and of Israel for generations to come”.

Aipac has remained silent on its rival from the left. But smaller Jewish groups known for their hawkish views have attacked J Street in recent weeks, arguing that it is not a true supporter of Israel.

One of them, Stand With Us, said in a statement: “We are most concerned because J Street frequently endorses anti-Israel, anti-Jewish narratives.”

Hadar Suskind, director of policy at J Street, said that those accusing it of being anti-Israel are wrong and some are “intentionally spreading falsehood” by misrepresenting the group’s views.

J Street expects more than 1,000 activists to attend its conference, which will begin on October 25. The administration announced it would send one of its most senior officials, National Security Adviser James Jones, but several key lawmakers pulled their names from the conference’s sponsoring committee at last minute.

Among them were New York senators Charles Schumer and Kirsten Gillibrand.

Both said they were unaware of being on the list of sponsors in the first place.