What is Constitution?
What is Interim Constitution?

A provisional constitution, interim constitution or transitional constitution is a constitution intended to serve during a transitional period until a permanent constitution is adopted.

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On 17th April 1972 an Interim Constitution was adopted by the National Assembly, which provided for a Presidential form of Government. Under this Constitution, the National Assembly was not to be dissolved earlier than 14th August 1973.

However, from 14th August 1947 to 1st March 1956 the Government of India Act, 1935, was retained as the Constitution of Pakistan.
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In the constitution making processes in the three constituent assemblies of Pakistan (1947-1954, 1955-1956, 1972-1973), producing the 1956 and (current) 1973 constitutions, the Islamic character of the state and federalism were the two vexatious questions that prevented the forging of consensus amongst them.
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Interim government refers to a temporary government that operates between permanent governments. Interim governments are also referred to as provisional governments and exist until the nation settles on a permanent government through the process of elections or negotiations.