Please prepare a contract of employment order mentioning the terms of contract and period of contract.
In the said contract of employment letter include a separation clause stating that the Organization reserves right to terminate their contract by giving 1 month written notice or pay lieu of that. Similarly if the opposite party wants to terminate the contract before the completion period they are also supposed to give one month notice in advance or one month in lieu of that.
So you cannot terminate the contract one fine morning without advance info. Either pay them one month pay or provide them one notice period with salary.
7th May 2019 From India, Madras