Exhibit 1

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                                                             Page 11 of 14 Pages

                                    Exhibit 1

                             AGREEMENT TO FILE JOINT
                           STATEMENTS ON SCHEDULE 13G


     THIS AGREEMENT is entered into as of the 10th day of February, 2000 by and
among Xxxx-Xxxxxx Asscher, a French citizen ("JCA"); Tekelec F, a French
corporation ("Tekelec F"); Natinco, S.A., a Luxembourg corporation ("Natinco");
and Xxxxxxx Xxxxx, a Swiss citizen ("Givel"), and replaces in its entirety that
certain Agreement to File Joint Statements on Schedule 13G, dated as of February
3, 1999, by and among Tekelec-Airtronic, S.A., a French corporation, Tekelec F,
JCA, Natinco and Givel.

                             W I T N E S S E T H

     WHEREAS, JCA, Tekelec F, Natinco and Givel may be deemed to have held or to
hold beneficial ownership, individually and/or in the aggregate, of more than
five percent of the shares of the Common Stock of Tekelec, a California
corporation (the "Common Stock"), as of December 31, 1999 and as of December 31
of each calendar year thereafter;

     WHEREAS, the Common Stock has been registered by Tekelec under Section
12(g) of the Securities Exchange Act of 1934 (the "Act");

     WHEREAS, pursuant to Rule 13d-1 under the Act, any person who holds more
than five percent of such a class of registered equity securities as of the end
of any calendar year is, under certain circumstances, permitted and/or required
to file with the Securities and Exchange Commission a statement on Schedule 13G;
and

     WHEREAS, Rule 13d-1(f) under the Act provides that, whenever two or more
persons are permitted to file a statement on Schedule 13G with respect to the
same securities, only one such statement need be filed, provided such persons
agree in writing that such statement is filed on behalf of each of them.

     NOW, THEREFORE, in consideration of the foregoing premises and the mutual
covenants and agreements contained herein, the parties hereby agree as follows:

     Each of JCA, Tekelec F, Natinco and Givel hereby agrees, in accordance with
Rule 13d-1(f) under the Act, to file jointly any and all statements and amended
statements on Schedule 13G (the "Statements") which may now or hereafter be
required to be filed by them with respect to the Common Stock beneficially owned
or deemed to be beneficially owned by each of them pursuant to Sections 13(d)
and 13(g) of the Act and the rules thereunder.



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     Each of JCA, Tekelec F, Natinco and Givel hereby agrees that such
Statements shall be filed jointly on behalf of each of them and that a copy of
this Agreement shall be filed as an exhibit thereto in accordance with Rule
13d-1(f)(iii) under the Act.

     Each of JCA, Tekelec F, Natinco and Givel agrees that neither this
Agreement nor the filing of any Statements shall be construed to be an admission
that any of JCA, Tekelec F, Natinco and Givel is a member of a group" pursuant
to Sections 13(d) and 13(g) of the Act and the rules thereunder.

     This Agreement may be executed in one or more counterparts which together
shall constitute one agreement.

     IN WITNESS WHEREOF, the parties have executed this Agreement or caused this
Agreement to be signed on their behalf by their duly authorized representatives
as of the date first above written.





Xxxx-Xxxxxx Asscher
------------------------------------------
Xxxx-Xxxxxx Asscher, on behalf
of himself and on behalf of Tekelec F





Xxxxxxx Xxxxx
-----------------------------------------
Xxxxxxx Xxxxx, on behalf of himself
and on behalf of Natinco, S.A.