UPDATE 1-Griffin Mining delays restart of Caijiaying mine ops

* Says plant upgrade work started later than expected

* Production to restart on June 1, rather than March 30 (Adds details)

March 27 (Reuters) - China-focused Griffin Mining Ltd (GFM.L) said it had slightly delayed the restart of operations at its Caijiaying zinc-gold mine as upgrade work at the plant started later than expected, and due to harsh winter weather.

The company now expects production from its main asset to restart on June 1, rather than March 30 it expected earlier.

Griffin had temporarily suspended production at the mine from the end of December 2008 to facilitate mine development.

The company said on Friday it expected the upgrade and maintenance work to be completed shortly. Griffin Mining shares closed at 23.75 pence on Thursday. (Reporting by Balachander Surianarayanan in Bangalore; Editing by Gopakumar Warrier)