ROTTERDAM, Netherlands (AP) — Dutch Prime Minister Mark Rutte says he was forced to keep two Turkish ministers from traveling within the Netherlands and to bar them from campaigning among Turkish voters because Ankara had threatened sanctions against his government.

Rutte said Sunday, "We can never do business under this kind of blackmail."

The prime minister says he was shocked to see one of the ministers try to get to a Rotterdam rally by car after the government had made clear she was not welcome.

Turkey's minister of family affairs was escorted back to the German border after a long standoff outside the Turkish consulate in Rotterdam.

Earlier, the Dutch government had withdrawn the landing rights of the plane carrying Turkey's foreign minister.

The ministers planned to urge Turkish expatriates to back the referendum, which would expand the president's powers.

Rutte says: "We drew a red line."