Toshiba said on Friday it would not be able to complete an $18 billion deal to sell its memory chip unit by an agreed deadline at the end of March, as it had not received anti-monopoly approval from China.

The company anticipates that closing of the transaction will occur in April 2018 or thereafter.

Failure to meet the deadline gives Toshiba the option of walking away from the sale of the world's No. 2 producer of NAND chips without penalty - a move that some investors have urged it to consider.

Toshiba agreed last year to sell Toshiba Memory Corporation, a wholly owned subsidiary of Toshiba, to K.K. Pangea, a special purpose acquisition company formed by a consortium led by Bain Capital Private Equity, L.P. a consortium.

Some activist shareholders oppose the sale, saying the $18 billion price tag undervalues the business and that Toshiba should renegotiate with the Bain group or consider an initial public offering.

Toshiba said there would be no impact on the FY2017 full year business results forecast that the company had announced on February 14, 2018, as it did not include anticipated effects from closing the transaction, such as profit from the sale.