KIEV, Nov. 27 ??“ The pro-government coalition will probably boycott President Viktor Yushchenko??™s plans to amend Ukraine??™s constitution, Deputy Parliamentary Speaker Adam Martyniuk said Monday.

Yushchenko created a constitutional commission seeking to amend the constitution by defining responsibilities between the president and the government in order to prevent a looming constitutional crisis.

???The president has no right to create constitutional commissions. Only Parliament has such power,??? Martyniuk said. ???That??™s why Parliament will not send its representatives to work in the commission.???

The coalition??™s refusal to cooperate with the president suggests that tensions will continue to rise between the two authorities that could evolve into the crisis.

Prime Minister Viktor Yanukovych has been already challenging Yushchenko by insisting that it is the coalition that must define the country??™s foreign and defense policies. Yanukovych, a pro-Russian figure, pledged to postpone Ukraine??™s accession to NATO, an alliance that Russia views as a military threat.

The constitution currently allows the coalition, led by the prime minister, to draft and implement economic and financial policies. But it gives the president the right to nominate foreign and defense ministers, a clear reference allowing the president to define the foreign and defense policies, Yushchenko??™s supporters say.

Yushchenko lost most of his earlier powers, such as ability to appoint and to dismiss Cabinet ministers, after controversial changes to the constitution had come into effect earlier this year.

The changes were approved in December 2004 as a compromise that had apparently averted police attacks on demonstrators during the Orange Revolution, a public uprising that had catapulted Yushchenko to the presidency.

The confrontation between the president and the government may force Yushchenko to launch referendum to approve the amendments, a plan that is likely to be opposed by the government.

Martyniuk said that only Parliament has to amend the constitution, even if the people approve the amendments at a referendum. ???Parliament got this power based on the results of the referendum,??? he said.

Roman Zvarych, Yushchenko??™s representative to Parliament, said the constitutional commission, which includes judges from the Constitutional Court, has already started to work.

???The possibility of approving the amendments at a referendum is currently being considered,??? Zvarych said. ???This wouldn??™t require a separate debate in Parliament.??? (tl/ez)