* Opposition sees electoral law challenge as a "coup"
* Demands reforms, full parliamentary system
* Emir says "incorrect" political practices hinder reforms (Adds Kuwait's ruler comments, Edits)
By Sami Aboudi
DUBAI, Aug 12 (Reuters) - The Kuwaiti government's efforts to change the electoral law before a vote expected this year amount to a "coup", opposition politicians said on Sunday, calling for political reform and full parliamentary democracy.
Kuwait, an OPEC member and U.S. ally in the Gulf, has been gripped by a political crisis that has hindered much-needed economic reforms. The crisis revolves around a row between the elected parliament and the appointed government led by Al Sabah ruling family.
On Sunday, Kuwait's emir Sheikh Sabah al-Ahmad al-Sabah urged unity, in comments that appeared aimed at ending the political bickering.
In June, the constitutional court effectively dissolved a parliament dominated by opposition Islamists and reinstated the previous, more government-friendly assembly. The dispute deepened last week when the government decided to refer the electoral system to the constitutional court.
"The majority bloc views what is happening as a real coup by the political authority against the constitutional system, a coup aimed at seizing the rights of the nation through the constitutional court," opposition politicians said in a statement released on Sunday after a meeting.
The reinstated parliament has failed twice in the past two weeks to swear in a new government as lawmakers boycotted the sessions, increasing the chances of a new election being called. Analysts say this could be after the Muslim holy month of Ramadan, which ends around Aug. 18.
The statement accused the government of dragging the judiciary into a political dispute over the boundaries of parliamentary constituencies that helped the opposition win a majority in elections in February.
"The political authority, through the constitutional court, is trying to create a legislative vacuum that will allow it ... to have control over the legislative decision-making process with the aim of controlling ... the outcome of any future parliamentary election to monopolise power," said the statement, published on the www.alaan.cc news website.
The opposition statement urged the supreme judicial council and the constitutional court not to hear the case. "Confronting the scheming of the authorities is the responsibility of the whole Kuwaiti people," it said.
EMIR WEIGHS IN
Kuwait has long prided itself on having a fully elected legislature and lively debate - unique in a region governed by autocrats who tolerate little dissent - but the ruling al-Sabah family still holds a firm grip on state affairs.
The most important cabinet posts are held by family members and the 83-year-old emir reserves the right to dissolve parliament at will.
On Sunday Sheikh Sabah blamed "incorrect political practices assumed by some for impeding development".
"We will not allow the continuation of such method and we will all work together ... on pushing forward with the development," he said in a televised speech.
"The given freedom and right of speech should not be used in a way that causes discord and harms the social fabric built by our fathers and forefathers," he said.
Opposition politicians said the response to the government plans was to mobilise popular opposition and renew demands for political reforms. "The opposition bloc sees that the popular effort should ... seek to revive the constitutional emirate to achieve an elected parliamentary government," it added.
Kuwait has not experienced the kind of mass popular uprisings that have swept the Arab region since last year, but tensions have grown between the cabinet and opposition lawmakers pushing for a say in government. The country has seen eight governments come and go in just six years due to bickering between the parliament and cabinet. (Additional reporting by Rania El Gamal; Editing by Alessandra Rizzo)