According to Bild, Schäuble spelled out his plan at a behind-closed-doors meeting of leaders of his conservative Christian Democratic Union (CDU) and its Bavarian sister party the Christian Social Union (CSU) yesterday (1 September).
Shifting greater powers over economic and financial policy to Brussels is necessary, he reportedly said, "even though we know how difficult a treaty change will be".
Some EU leaders, including Chancellor Angela Merkel, have argued that a treaty change could help enforce fiscal rules to avoid repeats of the debt crises plaguing members of the euro zone, including Greece, Ireland and Portugal, which have required costly bailouts.
"I will push for necessary treaty changes so that we can act sooner and more effectively when things go wrong, including with targeted sanctions," Merkel said at the time.
"Europe must learn the right lessons for the future [...] We have seen that the instruments of the euro zone as they currently stand are insufficient," Merkel said.
Schäuble, however, insisted that such reforms were needed even if they threatened to further divide the 17 EU member states that used the euro and the remaining 10 that did not.
The Treaty on European Union, signed in Maastricht in 1992, came into force in 1993, and making changes in the years since then has proven cumbersome and complicated.
The most recent example was the signing of the Lisbon Treaty, which was eventually ratified by all 27 member states after heated debate in some countries, especially those which were required to hold a referendum. One major stumbling block was the rejection of the treaty in a 2008 Irish referendum, which was reversed the following year in a second vote.
Schäuble's proposal may also face opposition in the Budestag, Germany's federal parliament, where some MPs have criticised the government's decisions over the eurozone bailouts.
