Explanation

In the 1973 war, Pakistan resigned from The SEATO.

SEATO is an abbreviation of South East Asia Treaty Organization

When the Vietnam War ended in 1975, the most prominent reason for SEATO's existence disappeared.

As a result, SEATO formally disbanded in 1977.

SEATO was founded on 8th September 1954 and dissolved on 30th June 1977.

In September 1954, the Southeast Asia Treaty Organization, or SEATO was formed by:

the United States,

France,

Great Britain,

New Zealand,

Australia,

the Philippines,

Thailand,

and Pakistan 

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