President-elect Donald Trump is weighing in on the intelligence community's investigation of alleged Russian hacking.

FOX's Rachel Sutherland reports from Washington:

The President-elect tweeted: "If Russia, or some other entity, was hacking, why did the White House wait so long to act?"

Attorney General Loretta Lynch told a "Politico" breakfast the administration has been looking at alleged Russian hacking for months:

(Lynch) "This was a grave concern to us. So we began in the summer to look at what we could say publicly about this issue."

The House Intelligence Committee canceled a planned briefing today. Republicans are upset the CIA wouldn't send anyone. Intelligence officials want to wait to answer questions on the matter until after they finish a White House ordered probe.

In Washington, Rachel Sutherland, FOX News.

Follow Rachel Sutherland on Twitter: @SutherlandFOX