The US Department of Justice has said that the federal courts in six US states have ordered allowing the Internal Revenue Service (IRS) to serve so-called "John Doe" summonses on US banks seeking information about unknown individuals who have used certain credit or debit cards in Norway.

At the request of the Norwegian government, the orders were issued over the last week in lawsuits filed by the IRS in Minnesota, Texas, Pennsylvania, Oklahoma, Virginia and California.

In total, 18 US financial institutions are identified in the government’s court filings. The filings do not allege that these financial institutions have violated any US laws with respect to these accounts.

Kathryn Keneally, assistant attorney general for the Justice Department’s tax division, said: "The Department of Justice and the IRS are committed to working with our treaty partners to fight tax evasion wherever it occurs. All taxpayers should know that our efforts in this area are global, coordinated and will continue."

The Justice Department said that the lawsuits are part of ongoing international efforts to stop tax evasion through the use of foreign accounts.