The Catalan CiU nationalist bloc and its parliamentary partner, the Catalan Republic Left (ERC), have begun to hunch down in their trenches, in preparation for a showdown with the central government over their plans to hold a vote on sovereignty for Catalonia next year.

On Monday, the two political forces officially created the so-called National Catalan Transition Council, which will help drum up support from opposition parties and society for the planned vote on independence.

The two pro-independence forces will draft a sovereignty declaration that they will present to the regional parliament on January 23.

The ongoing confrontation between the nationalists and the central government is expected to overshadow a ceremony today when Prime Minister Mariano Rajoy, who has warned against holding the vote without congressional approval, and premier Artur Mas of the CiU will meet to help inaugurate the new AVE high-speed rail line that will connect Barcelona, Girona and Figueres. The new route will eventually link to the French high-speed rail lines.

The pair, accompanied by Prince Felipe, will spend several hours together traveling the new route, which will give them time to talk about the pressing issues.

According to sources at the Moncloa prime minister’s office, Rajoy already knows that Mas won’t — for the time being — be going back on his plans to hold the sovereignty vote. But the prime minister’s strategy will consist of trying to start a new dialogue, including holding talks about improving a central financing scheme for the region.

One of the most bitter gripes among independence supporters is that the region brings in more revenue for the rest of the country while getting little in return.