11.13pm BST

We're going to wrap up our live blog coverage for the day. Here's a summary of where things stand:

• Iraqi security forces fought Isis-linked militants at an oil refinery and in the northwestern city of Tal Afar, one week after the militants began claiming Iraqi territory.

• The Baghdad government requested that the US conduct air strikes. US president Barack Obama was said to be weighing his options. The US TV networks reported the US was conducting surveillance overflights in Iraq.

• A meeting at the White House between the president and congressional leaders ended without reportable result. Obama reviewed "options for increased security assistance" to Iraq, the White House said.

• Long lines formed at gas pumps in Irbil in Kurdistan as security threats at refineries and oil ministry policy produced new scarcity – and much higher prices – in the fuel market in the north.

• Dozens of foreign workers from Turkey, India and China were feared abducted by militants, while other foreign workers, notably Europeans working for oil conglomerates, were evacuated.

• The United Nations on Wednesday upgraded Iraq’s latest crisis to a level 3 humanitarian disaster — its most severe designation.