The Supreme Court on Monday pulled up the Ministry of Defence over the delay in payment of arrears of One Rank-One Pension (OROP) to eligible pensioners of the armed forces and sought an explanation from the secretary concerned for issuing a communication extending the timeline for payments fixed by the court.On January 9, the top court granted time till March 15 to the Centre for payment of total arrears of OROP. But on January 20, the ministry issued a communication that the arrears shall be paid in four yearly installments which has been challenged by a group of ex-servicemen.