can husband nullify the transfer if wife refuses to sign in 2nd motion

In a divorce by mutual, where even wife is in Government service, the husband agrees to give/transfer a house in his name, the market value of which is nearly Rs. 70 lakhs to wife, as per law relating to transfer of property, for such divorce. Subject to the condition that (1) wife signs the divorce deed in court also and (2) to pay the husband Rs. 30 lakhs in two installments of Rs. 15 lakhs each. Wife pays Rs. 15 lakhs and signs the divorce petition. At the time of payment of 2nd installment of Rs. 15, if wife denys to pay the same. Whether the husband has right to nullify house transfer.