BERLIN — The leaders of Germany’s Green party are signaling that they may drop demands for a 2030 deadline to phase out combustion engines and shut coal-fired power stations as Chancellor Angela Merkel’s government-building efforts intensify.

Merkel’s conservatives, the pro-business Free Democrats and the Greens want to determine by mid-November whether there’s enough common ground for full negotiations on a coalition never tried in national government. They struggled to bridge differences during initial talks.

Greens co-leader Cem Ozdemir signaled in an interview with the daily Stuttgarter Zeitung published Tuesday that his party will soften its demand, much criticized by its prospective partners, to stop registering new cars with gas or diesel engines in 2030.

“It is clear to me that we alone will not be able to push through the cutoff date of 2030 for the registration of fossil-fuel combustion engines,” he was quoted as saying — though “we must of course clear the way for emissions-free mobility with binding measures.”

The party also has called for coal-fired electricity plants, currently a significant source of energy for Europe’s biggest economy, to be shut by 2030. But chairwoman Simone Peter told the Rheinische Post daily it is “pragmatic” on “whether the last coal-fired power station goes offline in 2030 or 2032,” and that the key is reducing carbon dioxide emissions.

Germany, which is currently hosting a global conference on combating climate change, will miss its own emissions reduction targets unless further measures are taken, officials say.

The Greens’ comments increase pressure on other parties to make concessions. There’s been little sign of movement so far, with Free Democrat leaders in particular saying they’re not afraid of new elections.

Polls suggest a new vote wouldn’t create a parliament much different from the one elected in September. In that election, the nationalist and anti-immigration Alternative for Germany, or AfD, emerged as the third-biggest party.

“We in AfD are not afraid — we would be very glad of new elections, because apparently none of the other parties is capable of fulfilling the task set by voters and forming a sensible governing coalition,” co-leader Alice Weidel said Tuesday.