Industry reports suggest Federal Communications Commission (FCC) chairman Julius Genachowski will officially announce his decision to step down today. The Wall Street Journal cites two unnamed sources for the story, one an FCC official.

The news, which has been rumoured for some time, comes days after Robert McDowell, a senior Republican commissioner on the FCC’s five-member panel, announced his decision to leave the US regulator.

According to rules governing FCC appointments, President Barack Obama will have to nominate a new Republican Commissioner and Democratic chair.

Genachowski’s tenure ends in June and follows a successful four-year term. Genachowski, appointed by President Obama in 2009, has been an eager supporter of freeing up more spectrum for wireless operators. Controversially, the FCC also blocked plans by AT&T to acquire T-Mobile USA during his tenure.

Reuters says there are several candidates to replace Genachowski. These include Tom Wheeler, a venture capitalist and an Obama ally and fundraiser. Another is Lawrence Strickling, head of the National Telecommunications and Information Administration. Karen Kornbluh (recently an ambassador to OECD), and Blair Levin, a former FCC staff member and now industry analyst, are also named by Reuters.