US stocks opened lower with global markets fell across the board. President Donald Trump stoked more worries over global trade at the weekend, vowing to double import tariffs on foreign steel and aluminum to 50%, with Canada’s industry minister warning that it would retaliate. There are also signs the US-China truce is at risk after Trump accused Beijing of reneging on an agreement reached last month.

Looking ahead, there are a slew of labor-market indicators due this week — including the May employment report — which will help to steer US monetary policy.

Russia and Ukraine will resume direct peace talks in Istanbul a day after Ukraine staged one of its boldest aerial attacks inside Russia, which destroyed long-range bombers and other aircraft.

Ukrainian Defense Minister Rustem Umerov will lead the talks Monday opposite a delegation headed by Russian presidential aide Vladimir Medinsky. The meeting marks only the second time the two warring sides have held public negotiations since the early days of the conflict and follows a first round of talks in May.

Prospects for peace remain distant despite months of high-profile efforts by US President Donald Trump, who has grown increasingly frustrated with the lack of progress. Moscow didn’t accept a US proposal for a 30-day ceasefire and has laid out maximalist demands to end its invasion, now in its fourth year. While Trump has threatened to impose more sanctions on Russia, he’s held off on taking that step.