A Republican senator said allegations that President Donald Trump directed hush-money payments to women during the 2016 election campaign are "concerning," but added that "we need to wait" for the entire picture.

Sen. Susan Collins of Maine told CNN's "State of the Union" that it was a bad week for the president, with Trump's former longtime attorney Michael Cohen getting sentenced to three years in federal prison after pleading guilty to nine felony charges earlier this year. Two of those charges were campaign-finance violations stemming from a pair of payments to women that Cohen said Trump directed him to facilitate just prior to the 2016 election.

Both Cohen and American Media Inc. — a publishing company that made one of the hush-money payments — told prosecutors the payments were made to benefit Trump's candidacy.

Collins told CNN's Jake Tapper, "There are a lot of unanswered ethical, legal and factual questions" surrounding the allegations. "But, clearly, this was not a good week for President Trump, nor for his campaign organization."

"These allegations are concerning," the Maine Republican said. "But we need to wait until we have the entire picture."

Collins also said it's "critical" for special counsel Robert Mueller, who is probing Russian interference in the 2016 election and possible collusion by Trump associates, "be allowed to complete his investigation unimpeded."

Tapper also brought up The Wall Street Journal's Thursday report that federal prosecutors are probing whether the Trump inaugural committee improperly spent funds, noting that now Trump's administration, campaign, transition team and inaugural committee as well as the Trump Organization and Trump Foundation are under investigation.

He asked Collins if she felt Trump had "respect for the rule of law" in light of all of those investigations.

“I think this reflects the fact that President Trump put together a campaign organization with very little experience, with completely inadequate vetting," Collins said. "And I think that's what happens. This is what happens when you take that kind of approach.”