A letter written and signed by George Washington concerning the US Constitution has sold at the top of Christie's Fine Printed Books and Manuscripts including Americana auction, which was held on June 21 in New York.

Any item from Washington relating to the creation of the Constitution is highly sought after

It sold for $1.4m, comfortably meeting the $1m-2m valuation.

Dated April 25, 1788 and written to revolutionary war officer John Armstrong, the seven-page letter sees the soon-to-be-president adding his positive views to the bitter and drawn-out debate over the Constitution's ratification.

He writes: "I doubt whether the opposition to the Constitution will not ultimately be productive of more good than evil", adding that the Constitution's framers "have thrown new light upon the science of government, they have given the rights of man a full and fair discussion."

Washington had retired to Mount Vernon at the end of the revolutionary war in 1783, but his esteem meant he was soon called upon to assist in the formation of the United States.

The delegates had designed the presidency with him in mind, and he was allowed to define the office once elected.

Letters from Washington on the creation and adoption of the Constitution are some of the most sought after of his memorabilia.

In December 2009, Christie's sold Washington's impassioned defence of the new Constitution to his nephew, Bushrod Washington, for $3.2m.

In June 2012, Washington's personal copy of the Acts of Congress, featuring his own annotations of the Constitution, became the most valuable American book or historical document ever sold at auction after realising $9.8m.

Paul Fraser Collectibles has this George Washington autographed lottery ticket for sale, as well as authentic strands of his hair.