EXHIBIT 4.3 CERTAIN PORTIONS OF THIS EXHIBIT HAVE BEEN OMITTED BASED ON A REQUEST FOR CONFIDENTIAL TREATMENT OMITTED PORTIONS HAVE BEEN SEPARATELY FILED WITH THE SECURITIES AND EXCHANGE COMMISSION MEMORANDUM OF AGREEMENT BETWEEN VIDESH SANCHAR NIGAM LIMITED (VSNL / INDIA) AND BRITISH TELECOMMUNICATION SERVICE LIMITED (UK - BT) 1. This memorandum between VSNL and UK-BT represents an agreement by VSNL and UK-BT to apply the following accounting rates and settlement method as specified below in paragraph 2 for settlement of International Telephone service between India and United Kingdom. 2. Total Accounting rates and the settlement of International Telephone service are agreed for the period beyond April 1, 2002 as follows: 2.1 PERIOD OF APPLICATION ACCOUNTING RATES ON SENDER PAYS TRANSIT BASIS 01-04-2002 ONWARDS SDR [TEXT REDACTED] P.M. SENDER PAYS TRANSIT 2.2 ACCOUNTING/SETTLEMENT PERIOD MONTHLY BASIS 3. The application period's accounting rates shall be applied to each conversation minute of International switch service (subscriber-dialed , operator-handled). 4. This agreement supersedes all prior agreements on the subject as indicated above between VSNL and BT (UK). This agreement shall become binding upon execution by the duly authorized representative of BT (UK) and VSNL and where applicable upon submission and /or acceptance of the agreement by regulatory authorities. 5. TAR to be reviewed in Sept. 2002. Signed for and on Behalf of Signed for and on Behalf of VSNL / India BT Telecom (UK) /s/ K.P. Tiwari /s/ Peter Nott - --------------------------- --------------------------- 1 K.P.Tiwari Mr. Peter Nott Executive Director (OPS) Managing Director VSNL, INDIA BT Global carrier services Date: 20/5/2002 United Kingdom 2