Microsoft is putting increased pressure on the US Bureau of Customs and Border Protection (CBP) to enforce an import ban on phones made by Google-owned Motorola Mobility, according to reports.

Reuters said the company filed a motion in a US court last week requesting that the agency enforce an import ban imposed by the US International Trade Commission (ITC) in May 2012.

The ITC ruled that Motorola infringed a Microsoft patent for generating and synchronising calendar items and barred devices that infringed the patent from being imported into the US. According to the court filing, the ban should have come into effect 60 days after the order was issued but it has yet to be enforced.

The Windows Phone maker said in its complaint that the CBP and Google held secret meetings which resulted in the agency continuing to allow the import of Motorola devices into the US. This is despite Google not having made efforts to remove the patented feature from devices.

Microsoft said CBP “has repeatedly allowed Motorola to evade that order based on secret presentations that CBP has refused to share with Microsoft”.

In a statement, Microsoft’s deputy general counsel, David Howard, said customs has “a clear responsibility to carry out ITC decisions”, and “repeatedly ignored its obligation and did so based on secret discussions”.

According to Bloomberg, Motorola successfully argued to the agency that the order did not apply to syncing through Google servers, with a grace period granted to allow changes to take effect. However, Microsoft said the ITC rejected both of these proposals.

For its part, Google has argued that Microsoft attempted to broaden the order beyond what the ITC intended.

Matt Kallman, a Google spokesman, said that US Customs “appropriately rejected Microsoft’s effort to broaden its patent claims to block Americans from using a wide range of legitimate calendar functions, like scheduling meetings, on their mobile phones”.

The import order is in effect until the patent expires in April 2018. An appeal in the ITC case is scheduled for 6 August.