NEW YORK — Fox News Channel is threatening to sue Internet gossip Matt Drudge for breach of contract for walking off the set of his eponymous weekly chatshow, the cable news channel said Tuesday.

Fox News Channel’s legal team issued Drudge’s agent George Hiltzik a letter Tuesday that details its claims of breach of contract and asks for a public apology. If Drudge does not comply, Fox News said it will pursue legal action.

The channel claims that Drudge’s contract gives the net editorial control of his show and prevents him from making disparaging remarks about the network and its employees. Neither Hiltzik nor Drudge were immediately available for comment.

The battle began over the weekend when Drudge refused to host his weekly yakker on Saturday after he was prohibited from using a graphic photo from the National Enquirer that showed a fetus undergoing emergency surgery for spina bifida. Fox execs feared that Drudge would use the shot as a jumping-off point to discuss partial-birth abortions.

As for this weekend’s show, Fox News spokesman Brian Lewis said the net “expects Matt to show up for work on Saturday.” But, unless Drudge apologizes, his show will likely be pulled. “It’s in the hands of his attorneys now,” a source said.

Drudge had previously informed Fox News Channel that he would not reup when his contract expires in February 2001.