In an open letter, it also sought a declaration of a definite date for the implementation of OROP.
The letter comes ahead of a rally on Sunday to be organised by another group of ex-servicemen.
Reminding that in September 2013 at Rewari rally, then Prime Ministerial candidate Narendra Modi had promised to look after armed forces personnel, retired and serving, when elected to power, the Akhil Bharatiya Poorva Sainik Seva Parishad said OROP is a "burning" and "emotive" issue.
Patil noted that Jaitley in his first budget speech had "assured all of us" about the implementation of OROP .
"However we now hear that your ministry, if not you personally, is delaying the implementation process and are exploring the possibility of combining the issue of 7th Pay Commission, or worse, just delay the announcement of OROP indefinitely," he said.
He said since Jaitley was aware of the angst and "pain" of ex-servicemen, the delay in announcement of OROP makes them wonder "whether the faith we had imposed in the BJP, the government of India and in you, has been misplaced".
It will be a sad day, the letter said, if the ex-servicemen have to resort to protests and hunger strikes to get their "rightful due".
Referring to the protest planned on June 14, the letter said that if the government implements OROP after that day, it will be seen as "buckling" under pressure of an agitation and opposition attack.
It further added that it will be most unfortunate for democratic India "if the opposition of this country uses ex-servicemen as a tool against ruling party".
