20% pay cut anounced in my company due to COVID-19

Hello, Mine is an engineering services company headquartered in the UK, the Global leadership team sits in the UK and all decisions are made from the UK. We have our company in India in Mumbai and my query is that recently due to the COVID-19 pandemic, our company has announced 20% paycut for all employees accross. They have specifially mentioned to apply 20% pay cut on the basic salary. Also, where there is a pension fund contribution for UK this should also be cut in line with base salary – for us this will mean PF which will be reduced. They have also mentioned that the other benefits have to be paid at 100% reference salary like HRA, Bonus, LTA, e.t.c So we have decided to reduce 20% of the Basic Amount but restore HRA (wherever applicable), LTA & Bonus at 100% of reference salary for all the employees. The effective salary cut on Gross CTC shall differ for each employee depending on his Basic component but shall not exceed 20%. PF shall be impacted as it cannot exceed 12% of Basic. But my concern is, are we legally allowed to reduce basic salary of employees? Is there any clause that will help save us in case we are doing wrong? Our PF consultant has suggested that yes we can reduce basic salary for everyone except for the ones whose basic is 15000 as per the PF act. Now i need your expert advice here to understand if we as an enployer can reduce the basic salary which results in reduction in PF. Pls help. Thanks much.