President Trump is holding firm in his economic plans, even as stocks opened Monday morning at a loss and discontent grew over the weekend with his tariff agenda.

He pushed back on criticism quickly Monday, calling on Americans to be patient. Later in the morning, he threatened an additional 50 percent tariff on China, which had responded last week to Trump’s 34 percent tariff on imports by implementing the same on American imports.

Amid the tariff tension, Trump’s Monday agenda includes a meeting with a key ally, Israeli Prime Minister Benjamin Netanyahu. He arrived at the White House early in the afternoon.

Congress also returns to work Monday. House Republican leaders are urging their members to adopt the Senate’s version of the budget resolution, passed early Saturday, which will tee up Trump’s ambitious legislative agenda.

And Republican senators are starting to line up support for tariff deals or a check on the president’s trade authority. Sen. Mike Lee (R-Utah) suggested the White House take a deal after the EU said Monday it was ready to negotiate. Meanwhile, seven GOP senators are backing a bipartisan bill that would require congressional approval for steep tariffs on allies.

Follow along all day for updates.