Is it possible to revise contract (after signature) currency in Fidic contracts?

The Contract Price shall be paid in the currency or currencies named in the Appendix

to Tender. Unless otherwise stated in the Particular Conditions, if more than one

currency is so named, payments shall be made as follows:

(a) if the Accepted Contract Amount was expressed in Local Currency only:

(i) the proportions or amounts of the Local and Foreign Currencies, and the fixed

rates of exchange to be used for calculating the payments, shall be as stated

in the Appendix to Tender, except as otherwise agreed by both Parties;

(ii) payments and deductions under Sub-Clause13.5 [Provisional Sums]

and Sub-Clause13.7 [Adjustments for Changes in Legislation] shall be

made in the applicable currencies and proportions; and

(iii) other payments and deductions under sub-paragraphs (a) to (d) of Sub-

Clause14.3 [Application for Interim Payment Certificates] shall be made

in the currencies and proportions specified in sub-paragraph (a)(i) above;

(b) payment of the damages specified in the Appendix to Tender shall be made in

the currencies and proportions specified in the Appendix to Tender;

c) other payments to the Employer by the Contractor shall be made in the

currency in which the sum was expended by the Employer, or in such currency

as may be agreed by both Parties;

(d) if any amount payable by the Contractor to the Employer in a particular

currency exceeds the sum payable by the Employer to the Contractor in that

currency, the Employer may recover the balance of this amount from the sums

otherwise payable to the Contractor in other currencies; and

(e) if no rates of exchange are stated in the Appendix to Tender, they shall be those

prevailing on the Base Date and determined by the central bank of the Country.