To: Foster Wheeler AG Sheffield Park Reading Berkshire RG2 9FW For the attention of: Michelle Davies With a copy to: Freshfields Bruckhaus Deringer LLP London, EC4Y 1HS For the attention of: Simon Marchant Freshfields Bruckhaus Deringer US LLP New...

Exhibit 2.2

28 March 2014

To:

Xxxxxx Xxxxxxx XX

Xxxxxxxxx Xxxx

Xxxxxxx

Xxxxxxxxx

XX0 0XX

For the attention of: Xxxxxxxx Xxxxxx

With a copy to:

Freshfields Bruckhaus Xxxxxxxx LLP

00 Xxxxx Xxxxxx

Xxxxxx, XX0X 0XX

For the attention of: Xxxxx Xxxxxxxx

Freshfields Bruckhaus Xxxxxxxx US LLP

000 Xxxxxxxxx Xxxxxx

Xxx Xxxx, XX, 00000

For the attention of: Xxxxxxx X. Xxxxxx

Dear Sirs,

Implementation Agreement

We refer to the Implementation Agreement dated 13 February 2014 (the “Agreement”) between AMEC plc (“AMEC”) and Xxxxxx Xxxxxxx AG (the “Company”). Words and expressions used but not defined in this letter agreement shall have their respective meanings in the Agreement.

In accordance with clause 3.2 and Schedule 3 of the Agreement, AMEC or the parties (as the case may be) are required to file notifications with Relevant Antitrust Authorities for the purposes of satisfying Condition 2 of the Agreement within certain specified deadlines.

Notwithstanding those provisions, and in consideration of the mutual obligations of the parties contained herein, the parties agree that AMEC or the parties (as the case may be) shall be required:

1. to file the first draft of the Form CO with the European Commission as promptly as reasonably practicable following the date of this letter agreement and in any event no later than 4 April 2014;

2. to file the required notification in South Africa as promptly as reasonably practicable following the date of this letter agreement, to use reasonable endeavours to file the required notification no later than 11 April 2014, and in any event to file the required notification no later than 18 April 2014;

3. to file the required respective notifications in Canada, Russia, South Korea, Turkey, Ukraine and Mexico as promptly as reasonably practicable following the date of this letter agreement and in any event no later than 25 April 2014.

For the avoidance of doubt, except as set out in the preceding paragraphs, this letter agreement is without prejudice to the terms of, and the rights and obligations of AMEC and the Company under, the Agreement, which remains in full force and effect.

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This letter agreement may be executed in any number of counterparts and by the parties in separate counterparts, each of which is an original but all of which together constitute one and the same instrument.

This letter agreement and any non-contractual obligations arising out of or in connection with it are governed by, and interpreted in accordance with, English law. Any dispute concerning contractual or non-contractual obligations arising out of or relating to this letter agreement will be exclusively settled by the courts of England.

Yours sincerely,

By	/s/ Xxxxxx Xxxx
	Name: Xxxxxx Xxxx
	Title: Company Secretary & General Counsel
For and on behalf of AMEC plc
Agreed and confirmed for and on behalf of Xxxxxx Xxxxxxx AG
By	/s/ Xxxxxxxx X. Xxxxxx
	Name: Xxxxxxxx X. Xxxxxx
	Title: Executive Vice President General Counsel & Secretary

Cc:

Linklaters LLP

One Xxxx Xxxxxx

Xxxxxx, XX0X 0XX

For the attention of: Xxxxxxx Xxxxxxxx and Xxxxx Xxxxxxx

Linklaters LLP

0000 Xxxxxx xx xxx Xxxxxxxx

Xxx Xxxx, XX, 00000

For the attention of: Xxxxx X. Xxxxxxxxxxx and Xxxxx Xxxxx-Xxxxxxxxx

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