India's main communist party is urging Prime Minister Manmohan Singh to delay implementation of a controversial nuclear deal with the United States for six months.

Communist Party of India leader Prakash Karat said Tuesday the government should wait until it resolves differences with leftist parties who oppose the U.S. nuclear deal.

A joint committee of India's government and its leftist allies will meet Wednesday to discuss the issue.

Indian leftists say the nuclear deal would bring India too close to the United States and undermine New Delhi's independent foreign policy.

Communist Party leader Karat has already threatened to stop supporting Mr. Singh's government if it pushes the U.S. nuclear deal through parliament.

Mr. Singh's ruling coalition could collapse without the backing of parliament's four communist parties.

The nuclear pact would give India access to American nuclear fuel and equipment even though it has tested nuclear weapons and has not signed the Nuclear Non-Proliferation Treaty.

The deal also would require India to comply with International Atomic Energy Agency safeguards and seek the approval of 45 nations in the Nuclear Suppliers Group.

Some information for this report was provided by AFP and Reuters.