Dick Cheney, the US Vice-President, made an unannounced visit to Baghdad today to put pressure on the Iraqi political leadership to heal the country's sectarian divide.

In meetings held this lunchtime, Mr Cheney demanded that Nouri al-Maliki, the Iraqi Prime Minister, and the Kurdish President, Jalal Talabani, increase their efforts to fight the insurgency and do more to effect a process of national reconciliation. As one of his officials told accompanying journalists: "It’s game time."

Among other observations, Mr Cheney objected to the Iraqi parliament's plan to take a two-month break this summer. Earlier, evidence of the strained tone between the US and Iraqi Governments surfaced when the recently appointed US Ambassador to Iraq said the planned holiday was "impossible to understand".

In a short news conference after their meeting, Mr Cheney and Mr al-Maliki both acknowledged difficulties in the current joint US and Iraqi attempt to bring order to Baghdad and the surrounding provinces.

After an initial fall in the number of attacks in February and March, the plan has been rocked by a series of spectacular bombings, including a suicide attack on the Iraqi Parliament and an al-Qaeda-claimed assault on a US base in Diyala. The instability became evident hours later when a mortar bomb exploded outside the US Embassy, rattling the building where Mr Cheney was holding his meetings, although no one was hurt.

Mr al-Maliki, whose competence and Shia allegiances have been questioned in Washington, said today that "the meeting with the Vice President paved a foundation for practical steps to support our efforts working on both the security front as well as the domestic political issues".

Mr Cheney limited himself to a brief statement, saying: "We talked about a way ahead in terms of our mutual interests."

Later, however, the Vice-President said he had detected a greater urgency on the part of Iraqi officials to try and bring about the political changes that America and Iraq hope will serve to lessen the violence.

"I did sense, today, a greater awareness on the part of the Iraqi officials I talked to of the importance of their working together to resolve these issues in a timely fashion," he said.

From the moment he touched down in Baghdad this morning, Mr Cheney spoke of action, greeting the top US commander in Iraq, General David Petraeus, and the US Ambassador, Ryan Crocker, with the words: "There’s a lot going on. This is a very important time. There’s a lot to talk about."

Meanwhile officials accompanying Mr Cheney briefed journalists saying that the Vice President, a fierce advocate of the four-year-old war, intended to use his visit to demand more from the Iraqi Government.

"We’ve got to pull together. We’ve got to get this work done. It’s game time," one official was quoted as telling the AP news agency.

When asked about the content of today's talks, Mr Crocker said that the American objection to the parliamentary recess would be spelled out.

"That’s clearly part of the message. It’s been part of the message now for some time. I’ve said it, Secretary (of State Condoleezza) Rice has said it. I’m confident the Vice-President is going to say it," said the ambassador.

"The reality is, with the major effort we’re making, (the) major effort the Iraqi security forces and military are making, themselves, for the Iraqi Parliament to take a two-month vacation in summer is impossible to understand."

Iraqi MPs are believed to have not yet made a final decision on whether to take August and September off, as had been initially planned, and this evening the Iraqi Defence Minister, Abdel Qader Jassim Mohammed, hinted that the holiday would be cancelled.

As the Vice-President made his visit, the scale of the task facing the coalition was once again made clear when two separate attacks killed a total of 23 people.

In one incident, four Iraqi journalists were killed when gunmen opened fire on their car in the northern city of Kirkuk. Police said that one of the reporters was the director of a local media organisation which publishes several newspapers.

Meanwhile, earlier in the day, a truck bomber killed at least 19 in the usually peaceful Kurdish city of Irbil. A further 70 were hurt in the explosion, which targeted the Interior Ministry offices in the town.

Asked whether Iraq was more secure today than on his last visit in December 2005, Mr Cheney said that commanders had told him the situation had improved but he conceded: "I have to rely on reports, just like everybody else, because obviously I spent today here basically in our embassy and military headquarters in the Green Zone so I can’t speak from personal experience to what’s going on all across Iraq."

The Vice-President's visit followed a video conference earlier this week between Mr al-Maliki and President Bush exploring ways to try to ease the Shia-Sunni friction in the country. After leaving Iraq, Mr Cheney is due to embark on a week-long tour of the Middle East which will take in stops in the United Arab Emirates, Saudi Arabia, Egypt and Jordan.

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