NEW YORK (Reuters) – Twitter Inc posted better-than-expected quarterly revenue and a surprise increase in monthly users on Tuesday, sending shares up 13 percent to a nine-month high as its campaign to clean up fake and abusive accounts continued to attract advertisers.

The microblogging site’s results caught the attention of U.S. President Donald Trump, a prolific tweeter with nearly 60 million followers, who called for the creation of “more, and fairer” social media companies, repeating his claim that Twitter is biased against Republicans, without presenting evidence.

Twitter’s monthly active users (MAU) rose 9 million to 330 million in the first quarter from the previous quarter, much better than Wall Street’s average estimate that it would lose 2.2 million users, according to IBES data from Refinitiv.