Amid escalating tensions between the U.S. and Iran, the Iranian government has revoked the press credentials of a New York Times reporter, effectively barring the journalist from covering the government for the past four months, the Times reported Tuesday.

The Times correspondent, Thomas Erdbrink, who is a citizen of the Netherlands, has been covering Iran for the Times since 2012. He’s been unable to work since February, the newspaper said. While it is unclear whether there is a correlation, the Erdbrink ban comes as the U.S. sends more troops to the region in response to apparent threats against U.S. personnel in the Middle East.

The Iranian authorities have reportedly assured the Times correspondent that his credentials would be restored, but have not yet explained the rationale for the revocation.