Lord McAlpine was a "man of integrity" who made a huge contribution to public life, Conservative Party chairman Grant Shapps has said.
The former deputy Conservative Party deputy chairman died last night in Italy at the age of 71.
"Lord McAlpine made a huge contribution to public life," Mr Shapps said.
"He was a man of integrity who had a successful career in both politics and business.
"He was a towering figure during the Thatcher era who did much for the Conservative Party and our country.
"My thoughts are with his friends and family."
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