Jack Straw, visiting Baghdad unannounced with Condoleezza Rice, his US counterpart, said on Sunday: "The United States and the United Kingdom are the people who liberated this country.
"American and British and coalition force blood has been lost in the cause of liberty.
"It's very important now that the Iraqis make progress, and I think we are entitled to say that the loss of American and British and coalition lives - and a huge amount of money has been spent here - is itself a reason for the Iraqi leaders to make swift progress.
"There is significant international concern about the time the formation of this government is taking.
"We will be urging the Iraqi leaders we see to press ahead more quickly."
The pressure from Rice, the US secretary of state, was equally bold and may prove irresistible.
"Your international allies want to see this done," she told Iraqi Sunni, Shia and Kurdish leaders on the delay of nearly four months in forming a government since election.
"The United States and the United Kingdom are the people who liberated this country"
Jack Straw, the British foreign secretary
Rice and Straw have also made their pressure on Ibrahim al-Jaafari, the interim prime minister, crystal clear, calling on him to step aside in the name of national consensus.
The chill was palpable when Rice and the embattled al-Jaafari exchanged small talk on a rainstorm raging outside as reporters looked on. The smiles were frosty, the body language awkward.
But when Rice met Adel Abdul Mahdi, the vice-president and losing SCIRI candidate in February - and a possible replacement for al-Jaafari - the tone was clearly warm. "It's wonderful to see you," Rice said.
Iraqi political sources said that Rice and Straw had told Jalal Talabani, the Iraqi president, that they hoped to see a prime minister who could unite Iraqis and said al-Jaafari did not fit the bill.