WASHINGTON – Congressional Republicans and Democrats on Tuesday tempered calls for an immediate vote to block a Dubai-based company’s takeover of some U.S. port operations as President Bush prodded them to avoid a confrontation.

Returning to the Capitol in force for the first time since news of DP World’s takeover broke, lawmakers from both parties criticized the White House for failing to let them know about the deal before it became public.

But many also said steps taken over the weekend by the White House and the United Arab Emirates company for a 45-day investigation of the transaction’s security issues reassured them and negated the need for legislation for now.

“We should allow that to proceed,” said Sen. Susan Collins, R-Maine, chairwoman of the Senate Homeland Security Committee.

Over the weekend, Senate Majority Leader Bill Frist, R-Tenn., brokered a deal between the company and the Bush administration to agree to a new investigation of security issues related to DP World’s plan to assume significant operations at six U.S. ports.

Republican leaders were looking to curtail a revolt by members of the president’s own party, and by Tuesday it appeared they had succeeded.

“I’m very pleased where we are today,” Frist said.

Some lawmakers, though, warned they would move forward with legislation if the upcoming 45-day investigation of security issues was cursory.

Rep. Peter King, chairman of the House Homeland Security Committee, said he would file a bill that could give Congress an opportunity to block the deal if lawmakers are dissatisfied with the results of the security review. But he suggested he would not urge an immediate vote on it.

“It has to be a weapon held in reserve to ensure there is a real investigation,” King, R-N.Y., told The Associated Press.

Although the new investigation has yet to begin, the president said he still supports DP World’s plan to assume control of operations now handled by a British company.

“My position hasn’t changed,” Bush said after an Oval Office meeting with Italian Prime Minister Silvio Berlusconi.

Bush, the final arbiter of the new investigation, suggested there was no reason to think it would produce any different outcome than the government’s initial review and urged Congress to be careful.

“What kind of signal does it send throughout the world if it’s OK for a British company to manage the ports but not a company that has been secured – that has been cleared for security purposes – from the Arab world?” he asked.

In an interview later with ABC News, Bush said he would stand by the deal, adding, “The only way it won’t happen is if there is a true security threat to the United States of America.”

Democrats accused the president of prematurely determining the outcome of an investigation that the administration should have done in the first place.

“Let’s have a real investigation and a vote here in the Senate,” said Senate Minority Leader Harry Reid, D-Nev. “What the president has agreed to is no review.”

“If the investigation proves to be a charade, if it’s not truly independent and thorough, then the bipartisan legislation that we introduced yesterday will pass through the Senate and the House like a hot knife through butter,” Sen. Charles Schumer, D-N.Y., said.

Lawmakers said the political uproar could have been avoided if the White House had kept lawmakers in the loop on the DP World deal.

Sen. Trent Lott, R-Miss., said the White House was “slow to react” to the criticism. Lott also called the president’s threat last week to veto legislation Congress passed “very unwise.” “It offended me. He threatened me,” Lott added.

Senate Armed Services Committee Chairman John Warner, R-Va., who has backed the White House on the DP World deal, said he found “flaws” in the Bush administration’s earlier consideration of it. He also expressed optimism the government will approve the transaction after a lengthier investigation.

Also Tuesday, Bush administration officials and the company’s chief operating officer, Edward H. Bilkey, sought to reassure lawmakers the deal was prudent.

Before the Senate Commerce Committee, Bilkey said DP World spends large amounts on security already and recognizes that its business would be significantly disrupted if any problems were traced to the company.

“We couldn’t afford for anything to go wrong,” Bilkey told senators.

In London on Tuesday, a high court judge delayed until Thursday a decision on whether to approve DP World’s takeover of Peninsular & Oriental Steam Navigation Co. Two shareholders and a joint venture partner of the British company objected to the deal. The judge had been expected to approve the deal Tuesday.

Associated Press writers Ted Bridis, Katherine Shrader and Lara Jakes Jordan contributed to this report.