"They were not. They were spying — a term I don't particularly like — on what the Russians were doing," Clapper told ABC.
Clapper went on saying that the FBI was seeking to determine to what extent Russia tried to influence the US presidential election, including its attempts to gain access and leverage.
On Monday, the US Department of Justice instructed its Inspector General to expand the FBI and Justice Department's Russia investigations to examine any problematic tactics used against the Trump campaign.
The action came after Trump wrote in a Twitter post that the Justice Department and the FBI infiltrated his campaign for political purposes at the request of former President Barack Obama.
READ MORE: Trump to Ask Justice Dept to Probe if FBI "Infiltrated, Surveilled" His Campaign
Special Counsel Robert Mueller is investigating alleged Russian interference in the 2016 US presidential election, as well as accusations of collusion between Trump and Moscow, which both Russia and the US leader have repeatedly denied.
READ MORE: White House: DoJ Expands Probe Into 2016 Trump Campaign