Can the company change the proportion of basic salary to gross salary?

Dear Madam,

Our management has decided to change the salary structure where we used to pay 60% of Gross Salary as Basic Salary.

Now the management wants to change the basic salary of employees to 40% and the remaining amount to be included as other allowance.

There will not be any decrease in the salary but there will be a change in the basic salary percentage, is this allowed in the UAE (Our company is in Dubai, a mainland company, sole establishment)?

Is it legal to take this step?

If yes, then under which article can the change take place?

Do we need to settle gratuity based on the current basic salary and revise the contract or we can just change the basic as we are not reducing the gross salary?

Please advise.