President Trump questioned on Monday why the Obama administration began an investigation against his campaign before the November 2016 election, claiming the only purpose was to discredit the Trump campaign with no proof of wrongdoing.

The president also claimed the investigation, which he says was opened in order to get Hillary Clinton elected, was a bigger scandal than Watergate.

Trump’s tweet was also another attempt to distance himself from claims that he colluded with Russia, and to instead blame former President Barack Obama for not doing anything about Russian election meddling before the 2016 presidential elections. After the election, the Obama administration issued new sanctions, expelled Russian diplomats and closed two Russian diplomatic compounds in the U.S.

“Why did the Obama Administration start an investigation into the Trump Campaign (with zero proof of wrongdoing) long before the Election in November? Wanted to discredit so Crooked H would win. Unprecedented. Bigger than Watergate! Plus, Obama did NOTHING about Russian meddling,” Trump tweeted Monday morning.