A high-level adviser to Hillary Clinton's presidential campaign lamented the former secretary of state's "naïve sounding" comments about Russian President Vladimir Putin made during a speech before Goldman Sachs executives three years ago, leaked emails show.

Mandy Grunwald, Clinton's senior communications adviser, warned other staffers in January that Clinton's statements about Putin in closed-door remarks to Wall Street bankers could create "issues" for her on foreign policy, according to an email published by WikiLeaks on Monday.

"It's pretty bad," Grunwald wrote on Jan. 23, 2016, in response to an email circulating transcripts of Clinton's three speeches to Goldman Sachs executives in 2013. She singled out problematic comments made by Clinton about Dodd-Frank and Obamacare, as well as some related to foreign policy.

"And a ton of foreign policy stuff, including some naïve sounding comments about Putin—that could cause a whole separate set of issues—but Jake should review all that," Grunwald wrote, referring to Jake Sullivan, Clinton's foreign policy adviser.

The email with the transcript attachments was released by WikiLeaks in a previous trove of Podesta emails. According to the transcripts, Clinton said during a keynote speech at a Goldman Sachs conference on June 4, 2013, that she would "love" to build a more positive relationship with Russia and Putin.

"Look, I would love it if we could continue to build a more positive relationship with Russia. I worked very hard on that when I was secretary, and we made some progress with [Dmitry] Medvedev, who was president in name but was obviously beholden to Putin, but Putin kind of let him go and we helped them get into the [World Trade Organization] for several years, and they were helpful to us in shipping equipment, even lethal equipment, in and out of out of Afghanistan," Clinton said, according to the leaked transcript. "So we were making progress, and I think Putin has a different view."

Clinton was a chief player in the Obama administration's failed Russian "reset" in 2009 during her tenure as secretary of state. Since then, relations between the United States and Russia have deteriorated over Russia's 2014 annexation of Ukraine's Crimean Peninsula and the ongoing conflict in Syria, where Moscow has intervened militarily to prop up Bashar al-Assad.

Clinton delivered the speech at the June 2013 Goldman Sachs conference months before Russia staged a military intervention in Ukraine and seized Crimea.

"Certainly he's asserted himself in a way now that is going to take some management on our side, but obviously we would very much like to have a positive relationship with Russia and we would like to see Putin be less defensive toward a relationship with the United States so that we could work together on some issues," Clinton further stated, according to the transcript. "We've tried very hard to work with Putin on shared issues like missile defense. They have rejected that out of hand."

"So I think it's what diplomacy is about," she continued. "You just keep going back and keep trying. And the president will see Putin during the G-20 in Saint Petersburg, and we'll see what progress we can make."

Clinton's other Goldman Sachs speeches, both delivered in October 2013, did not contain substantial references to Russia or Putin. Grunwald sent the email months before Clinton beat Sen. Bernie Sanders (I., Vt.) for the Democratic nomination.

Tensions between the United States and Russia have grown strained in recent weeks, following the collapse of a ceasefire deal in Syria. Russia has curtailed its cooperation with the United States on nuclear matters, including by suspending a pact meant to clean up weapons-grade plutonium.

This month, the U.S. government also formally blamed Russia for directing the hacks of the Democratic National Committee and other U.S. political organizations in order to influence the presidential election. Clinton has used the development to tie Republican nominee Donald Trump to Putin. Some involved in Trump's campaign have also been found to have ties to Russia, including former campaign chair Paul Manafort.

The DNC emails were also published by WikiLeaks earlier this year, though the organization has denied having ties to Russia.

Clinton's 2013 speeches also featured extensive comments about China and its then-new president Xi Jinping, whom she described as a "more sophisticated, more effective public leader" than his predecessor, Hu Jintao.

The Clinton campaign did not return a request for comment by press time.