London(CNN) Theresa May railed against the forces of "absolutism" in politics, condemned the rise of populist parties around the world, and lamented her inability to secure Britain's exit from the European Union, in her last major speech as British Prime Minister.
In a final attempt to sculpt her own political legacy, May targeted politicians of the far left and urged a softening of political discourse from leaders and the public alike -- suggesting that an entrenchment of extremist positions doomed her repeated attempts to achieve Brexit.
She also criticized isolationist worldviews and stressed the importance of protecting the Paris Climate Accord and the Iran Nuclear Deal, in what will widely be seen as a rebuke of US President Donald Trump's foreign policy and his skepticism of international alliances.
"Both domestically and internationally, in substance and in tone, I am worried about the state of politics," May said in valedictorian-style remarks at foreign policy think tank Chatham House. "The values on which all of our successes have been founded cannot be taken for granted.
"The spirit of compromise in the common interest is also crucial in meeting some of the greatest global challenges of our time," she added, attempting to promote for a final time her own mantra of pragmatism and moderation.
May will step aside when the winner of the ongoing Conservative leadership contest is announced next week, bringing to an end a three-year tenure that will be defined by her inability to take Britain out of the EU.
"I'm deeply disappointed that I couldn't deliver Brexit... I did everything I could," May said. I put my own job on the line in order to do that." She added her belief that "most people across our country had a preference for getting it done with a deal."
"The problem was that when it came time for Parliament to ratify the deal, our politics retreated back into its binary pre-referendum positions -- a winner takes all approach to leaving or remaining," she reflected. "When opinions have become polarized -- and driven by ideology - it becomes incredibly hard for a compromise to become a rallying point."
The outgoing leader again expressed her belief that a no-deal Brexit would be an unfavorable outcome, but refused to cite her likely successor, Boris Johnson, as a partial source of her concerns. Johnson has repeatedly said he would be prepared to pursue a no-deal scenario.
She instead kept her criticisms general and wide-ranging, particularly when condemning the hardening of debate that has accompanied her time in power.
"Today an inability to combine principles with pragmatism and make a compromise when required seems to have driven our whole political discourse down the wrong path," she said.
"It has led to what is in effect a form of absolutism -- one which believes that if you simply assert your view loud enough and long enough you will get your way in the end. Or that mobilizing your own faction is more important than bringing others with you."
"This is coarsening our public debate," May added. "Some are losing the ability to disagree without demeaning the views of others."
She partially acknowledged a role in crafting that state of affairs, admitting when pressed by reporters that language used amid her fiery criticism of lawmakers during the Brexit impasse earlier this year hadn't been "perfect."
Elsewhere, May took the opportunity to criticize the "once-great" opposition Labour Party, and took direct aim at Russian President Vladimir Putin's suggestion that liberalism has "outlived its purpose."
And May expressed regret over President Trump's decisions to withdraw from international treaties, in particular the nuclear agreement with Iran.
"It took painstaking pragmatism and compromise to strike that deal," she said. "Whether we like it or not a compromise deal remains the best way to get the outcome we all still ultimately seek -- to prevent Iran from acquiring a nuclear weapon, and to preserve the stability of the region."
May has expressed her intention to return to the Conservative backbenches when her eventful and frequently agonizing residence in Downing Street comes to an end.
And, quoting Dwight Eisenhower's praise of a "middle of the road" approach, she signaled that she will continue to press for moderate policies -- an indication likely to be tested when her successor brings Brexit back atop the political agenda.
"I believe that seeking the common ground and being prepared to make compromises in order to make progress does not entail a rejection of our values and convictions by one iota, rather it is precisely the way to defend them," May concluded.