Colombo, Aug 3 (IANS): Sri Lanka's main Tamil party said on Monday it will not join a united government if it fails to address the grievances of the Tamils.

The Tamil National Alliance (TNA), which holds 14 seats in the 225-member parliament, said it hopes to win at least 20 seats in the parliamentary elections of August 17.

The battle to form a new government will be waged between the newly formed United National Front (UNF) coalition of Prime Minister Ranil Wickremesinghe and the United People's Freedom Alliance (UPFA), whose chairman is President Maithripala Sirisena.

Both Wickremesinghe and Sirisena have pledged to form a united government with the inclusion of all political parties including the minorities if either of them win the August polls.

"We will not join the united government till the Tamil issue is addressed. But if the UNF wins, we will offer our support to them from (the) outside.

"If Sirisena's UPFA wins, then it is difficult for him to form a united government as Mahinda Rajapakse has clearly stated that he wants a UPFA government," TNA candidate Suresh Premachandran told Xinhua.

Former President Rajapakse, who will be contesting the elections as a UPFA candidate, has rejected the idea of forming a united government.

The opposition remains split with a group of members backing President Sirisena and another group supporting Rajapakse.