Israeli Foreign Minister Avigdor Lieberman on Monday slammed the decision of the Swiss-based Inter-Parliamentary Union to invite the Palestinian Islamist movement Hamas to attend its 2012 session.
"This is just another example of international hypocrisy," Lieberman told Israeli public radio.
"In all international organisations, the 57 Muslim countries and the many non-aligned nations have the majority and consistently take anti-Israel positions," he charged.
A three-member delegation of MPs from Hamas's Change and Reform party left Gaza on Thursday for the meeting in Geneva, marking the first time parliamentarians from the Islamist movement will attend a session of the IPU.
In a statement, the MPs said they planned to discuss "Zionist crimes against (Hamas) members of parliament, in particular their kidnap and deportation."
They were to also to hold a series of official and public meetings, it said, without giving details.
The Israeli parliament, the Knesset, is also a member of the IPU and reportedly invests an annual sum of 250,000 shekels ($65,000/51,300 euros) in the body, the radio said.
Lieberman said there would be no immediate move to withdraw Israel from the IPU, but parliament speaker Reuven Rivlin said he was disappointed the organisation had agreed to host Hamas members.
"The president of the IPU, Anders Johnsson, promised me at a meeting last month in Geneva that he would not help Hamas gain international recognition," he told the radio.
The IPU encourages dialogue between MPs from parliaments around the world in a bid to promote "peace and cooperation among peoples" and "the firm establishment of representative democracy."