Lego was unavailable for comment and Starcom Motive declined to discuss its reasons for dropping out at the time of writing.
Lego's newly appointed global marketer, Mads Nipper, who recently axed three marketing divisions, is overseeing the review.
The struggling Danish toy maker is believed to be talking to at least three other media agencies, including Carat and MediaCom, and a decision is thought to be imminent.
Starcom Motive held the account in eight European markets. A further four markets: Germany, France, Italy and Spain are also up for grabs. The UK chunk of the account is understood to be worth around £7m.
The review follows a difficult time for the toy manufacturer after it reported annual losses last year of £127m.
It also confirmed that it was to axe 600 jobs earlier this year, as part of an ongoing restructure of the business. Lego has blamed its poor show on an over-reliance on licences and not concentrating enough on its core building-brick product.
Meanwhile in the US, The Lego Company has contacted three New York agencies regarding its $30m US media account.
The incumbent there is also Starcom. According to US sources, agencies contacted include WPP Group's Mediaedge:cia and Aegis Group's Carat.
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