The government of former Prime Minister Tony Blair had pledged to hold a public referendum to decide on the adoption of the Euro should "five economic tests" be met, to increase the likelihood that any adoption of the euro would be in the national interest. In addition to these internal (national) criteria, the UK would have to meet the European Union's economic convergence criteria (Maastricht criteria) before being allowed to adopt the euro. The Conservative and Liberal Democrat coalition government (2010–2015) ruled out joining the euro for that parliamentary term.