Though the cabinet committee on political affairs discussed the issue on Thursday, the decision has been left to the Congress Core Group headed by Sonia Gandhi, sources said.
The Congress party had earlier said the party would back the Prime Minister's decision on whether to attend the meet or not in Colombo from November 15 to 17.
The core group meeting also comes in the wake of some Union ministers and Tamil parties opposing PM's participation. The government is in a spot over the issue with some sections feeling the PM's absence at the CHOGM could affect India's image internationally and India would also miss a chance to push for the cause of Tamil population there.
The issue was discussed last month also by the Core Group and Union ministers P Chidambaram and AK Antony are learnt to have suggested that the PM should not visit Colombo to attend the meet.
Congress has so far refused to publically take a stand on the politically-sensitive issue and said on Wednesday that it will back whatever decision Manmohan Singh takes on India's participation in the summit keeping in mind the national interests.
Union ministers V Narayanasamy, Jayanthi Natarajan and GK Vasan have publicly opposed the Prime Minister's participation in the summit. Political parties and various outfits in Tamil Nadu are strongly opposed to India's participation in CHOGM and Tamil Nadu assembly had recently adopted a resolution demanding New Delhi shall completely boycott it and also suspend Sri Lanka from the Commonwealth till Colombo ensured equal status for Tamils.
CPI leader D Raja opposed PM attending the meet. Meanwhile, the BJP on Thursday expressed concern over the plight of Sri Lankan Tamils but remained non- committal on whether Prime Minister Manmohan Singh should attend the CHOGM in Colombo.
BJP chief Rajnath Singh held detailed deliberations on the issue with party leaders from Tamil Nadu, sources said. They said Singh gave a patient hearing to BJP Tamil Nadu chief Pon Radhakrishnan and leaders Ganeshan and Lakshmanan on the issue. These leaders demanded that the party should put pressure on the government that the PM should not attend the CHOGM to be held from November 15-17.
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