In June 2012, Argentina's President Kirchner attempted to thrust into the hands of David Cameron documents which called for UN talks on the sovereignty of the Falklands Islands.
Read: Deputy Political Editor Chris Ship's report on the incident which occurred at a meeting of G20 leaders in Mexico.
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The talks descended into crisis on Friday when Canada's trade minister Chrystia Freeland walked out of meetings.
Police in New York are still investigating what the substance is and whether it could be harmful.
The Sherlock actor made the comment while he received an award for his humanitarian work.