US President Barack Obama faces the unenviable task of handing power over to a man he once termed unfit for high office and who now vows to roll back much of the sitting president's legacy on both domestic and foreign policy. Despite repeated calls for a smooth transition of power, disagreements on Russian interference in the US presidential election and policy towards places like Israel and China have shown the cracks in the facade. Republican president-elect Donald Trump has said that, in his first 100 days, he wants to take steps to withdraw the US from the Trans Pacific Partnership trade deal with 11 other nations, dismantling one of the pillars of Obama's foreign policy and his focus on Asia. Trump has also called into question US recognition of the long-standing One China policy, by taking a call from Taiwan's leader. In another break from existing policy, he has vowed to relocate the US embassy in Israel to Jerusalem from Tel Aviv. Indeed, Trump has broadly characterized Obama's foreign policy as a "disaster." That leaves Obama with some work to do if he wants to protect his legacy. At home, Obama has been working to make the case for Democratic lawmakers and an army of citizen activists to push to maintain his keynote policy, on health care reforms. "What we do now determines how we'll rebuild and reimagine our party, and how we will fight back against any efforts to undermine the work that we have done together," Obama said in an email to supporters ahead of a speech Tuesday outlining his vision for the future. He has been less vocal about the state of his international agenda, with the White House both stressing long-standing bipartisan agreement on the underpinnings of US foreign policy and throwing up its hands when asked what the next administration may change. It all means the fate of Obama's major accomplishments on the world stage remains unclear, particularly given the complexity of some of the international agreements involved. Much may rest in the hands of the allies with whom Obama pursued some of his signature efforts, such as a global climate change agreement and a deal on the Iranian nuclear program. A lot of Obama's policy has been based on international cooperation, a strategy he defended at the United Nations in September as he denounced the isolationist desire to build walls and retreat from the world stage. Trump has been highly critical of the international deals needed for agreements like the one designed to prevent Iran from getting a nuclear weapon as well as the US rapprochement with Cuba. What is less clear is what he intends to do about the agreements. For example, Trump has signalled he will take a tougher line against terrorism and the fight against ISIS, but has so far provided few to no details about how he intends to do so or how he will handle the Syrian civil war. Obama's handling of the situation has come under fire since drawing a "red line" over the Syrian regime's use of chemical weapons in 2013, only to back down. The president expressed regret at a year-end press conference for the loss of life in Syria, but insisted there was little more he could have done without drawing the US into another costly ground war in the Middle East. The situation in Syria, along with the ongoing presence of US troops in Iraq and Afghanistan and the failure to close Guantanamo Bay prison remain unfinished business for Obama, leaving his successor with many of the same challenges he faced when taking the reins eight years ago. That, in and of itself, could create some problems if one believes Obama's own words. The president warned frequently of Trump's temperament during the campaign, though he has been quiet about those concerns since Trump's upset in November. However, Obama has not held back on the most prominent point of disagreement between his administration and Trump - Russia. Trump has vocally questioned intelligence showing Russia was behind the hacking of Democratic Party emails during the campaign and sought to help bolster the Republican candidate. "We have to remind ourselves we're on the same team. Vladimir Putin's not on our team," Obama said in an interview on Sunday. Trump had signalled he was open to closer relations with Moscow, but Obama has warned Trump not to throw US traditions to the wind.