A total of 28 Syrian opposition groups and parties announced Saturday the indefinite postponement of the long-awaited National Conference for Rescuing Syria, which was slated for September 23.

A statement issued on Saturday by the 28 opposition groups at a press conference in the Syrian capital of Damascus said the conference has been delayed "to avoid any step that might lead to strengthening the division of the national opposition and prolonging the Syrian crisis and its high costs on our people and homeland."

The National Conference for Rescuing Syria was called for by the oppositional National Coordination Body (NCB) and more other 20 opposition parties and groups.

Barwin Ibrahim, an opposition figure, said during the press conference that one of the main reasons behind the postponement is some differences between various opposition parties and the NCB regarding the vision and basics put forward by the NCB.

She said the NCB declared that it is against the militarization of the crisis while at the same time recognizes the rebels' Free Syrian Army.

Barwin also criticized the NCB for blaming only the Syrian government army for the violence in Syria without assigning blame on the armed rebels and the parties that are committing terrorism in the country.

"If the Syrian troops went back to their barracks, will the National Coordination Body be able to stop the Free Syrian Army?" Barwin questioned.

The postponement may further deepen the crack among the fractured opposition parties, which have so far failed to forge a united front to face the government of Syrian President Bashar al- Assad despite the numerous international endeavors.

Three members of the NCB disappeared Thursday after arriving at the Damascus international airport from a visit to China. Syrian information ministry said Friday that the three missing opposition figures were kidnapped by "terrorists," adding that the authorities had unleashed a wide-scale investigation and called on the kidnappers to release them.

The NCB said it could not get hold of the party responsible for the kidnapping, adding that it had informed a number of foreign embassies and national figures in and outside the country in hopes of knowing what happened to the three members.

No party claimed responsibility for the kidnapping, but it came apparently to hinder the start of the National Conference for Rescuing Syria. The conference was expected to bring together a considerable number of opposition figures from both in and outside Syria who hope to craft a solution to the protracted crisis.