BRUSSELS, Dec 16 (Reuters) - European Union leaders reiterated on Thursday their political commitment to finishing the bloc"s banking union, but set no date for it, underlining the deep disagreements between governments on what needs to be done to get there. The EU"s banking union is now set up for the 19 countries sharing the euro but non-euro zone members of the 27-nation bloc can join too. The project is to make the euro zone"s banking system safer and more resilient to crises. Under the banking union, all the major euro zone banks have a single supervisor - the European Central Bank - and a single resolution authority that is to wind down failing euro zone banks in a uniform manner. What is missing is a single deposit guarantee scheme that would ensure that any bank in any euro zone country would always pay out to its clients deposits up to 100,000 euros ($113,300) - a guarantee that would help prevent bank runs even in a major banking crisis. Calls to complete the banking union mean setting up the deposit guarantee scheme, but euro zone finance ministers have made little progress. Leaders asked them on Thursday only to draft a plan to get there, rather than find a full solution now. The main problem is that, before any deposit scheme can be set up, Germany wants euro zone banks to be less in danger of collapsing in the first place. This means reducing their bad loans and exposure to the debt of a single issuer, such as the government of the country where they operate, so that they would not go under if the sovereign they are most exposed to cannot redeem its bonds. Limits on the amount of bonds of a single sovereign that a bank is to hold are hard to swallow for Italy, which finances a lot of its borrowing in local banks. Some other southern countries share Italy"s objections. ($1 = 0.8826 euro)