US President Barack Obama on Saturday called on Britain and the European Union to get their divorce "right," saying that the world economy is at stake, according to dpa. Obama said he expects Britain to follow through on its shock decision to leave the EU given the high attention, "lengthy" campaign and high participation rates in the Brexit referendum. "How that process unfolds, how the negotiations work I think is going to be up to the parties involved," the president said, speaking in the Polish capital Warsaw at the end of at two-day NATO summit. "Our primary interest is to make sure that the negotiations and this process are as orderly and as sensible as possible, recognizing that it is in the interest of both sides to get it right," he added. "It's important that neither side harden positions in ways that ultimately do damage to their respective economies and ultimately to the world economy, at a time when our world economy is still pretty wobbly in places," the president said.