Exhibit 10.3

THE SYMBOL “[****]” DENOTES PLACES WHERE CERTAIN IDENTIFIED INFORMATION HAS BEEN
EXCLUDED FROM THE EXHIBIT BECAUSE IT IS BOTH (i) NOT MATERIAL, AND (ii) WOULD
LIKELY CAUSE COMPETITIVE HARM TO THE COMPANY IF PUBLICLY DISCLOSED

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June 12, 2018

Business Confidential Proprietary Information
Ms. Maria Vladimirova
Commercial Director
Joint Stock Company “TENEX"
28, bld. 3, Ozerkovskaya nab.
Moscow, 115484, Russia

Re:
1.    Enriched Product Transitional Supply Contract, dated March 23, 2011,
between Joint Stock Company “TENEX” (“TENEX”) and United States Enrichment
Corporation (“USEC”), TENEX Contract No. 08843672/110033-051, USEC Contract No.
EC-SC01-11-UE-03127 (the “TSC”)

2.    Letter Agreement, between TENEX and USEC, dated August 1, 2016, re: the
TSC (the “Feed Letter Agreement”)

Dear Ms. Maria Vladimirova:

United States Enrichment Corporation (“USEC”) proposes that, by execution of
this letter agreement and notwithstanding anything to the contrary in the TSC or
the above-referenced Feed Letter Agreement, TENEX and USEC hereby agree to
modify Paragraph 3 of the Feed Letter Agreement, by changing “June 30, 2018” to
“September 30, 2018”. During this period, USEC shall not [****]. This short
extension of the Letter Agreement is intended to give USEC and TENEX an
opportunity to complete a longer extension.

This letter agreement supplements and amends the TSC and the Feed Letter
Agreement, and unless it expressly states that it applies notwithstanding a
contrary provision of the TSC or the Feed Letter Agreement, this letter
agreement shall control to the extent that it is not consistent with an express
term of the TSC or the Feed Letter Agreement. All capitalized terms not defined
in this letter agreement shall have the meanings ascribed to such terms under
the TSC or the Feed Letter Agreement.

Please indicate your agreement to all of the above by signing on behalf of TENEX
in the space provided below. This letter agreement shall be effective as of the
first date by that TENEX and USEC have signed in the space provided. The letter
agreement may be signed in counterparts and delivered by any of the means
permitted by Section 16.01 of the TSC, including by electronic mail in Adobe
portable document format (.pdf) to the electronic mail addresses in Section
16.01. A counterpart document (including in .pdf format) signed by a Party shall
constitute an original and all such signed counterparts assembled together shall
constitute a fully executed agreement.

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Sincerely,

/s/ Elmer Dyke

Elmer Dyke

Signed on behalf of the Joint Stock Company “TENEX”

/s/ Maria Vladimirova________________________
(signature)

Maria Vladimirova                    
(name)

Commercial Director     
(title)

June 20, 2018                        
(date)