* European shares snap six-day winning streak
* Oil slumps as Libya restarts oilfields (Updates with U.S. market open, changes byline, dateline; previous LONDON)
By Chuck Mikolajczak
NEW YORK, April 27 (Reuters) - Key world stock markets dipped on Thursday after a three-day rally in the wake of a largely expected U.S. tax cut plan, while the euro weakened after comments from European Central Bank President Mario Draghi.
On Wall Street, stocks edged lower after a lukewarm reception for U.S. President Donald Trump's tax plan unveiled on Wednesday, some of the details of which were largely expected by investors.
The plan proposes deep U.S. tax cuts, many for businesses, that would make the federal deficit balloon if enacted. The market now is waiting to see if the proposal will become law.
"It is getting to the point, this may be the last sort of hurrah for the hope trade – the announcement of the tax cut," said Tom Siomades, head of the Investment Consulting Group of Hartford Funds, in an interview with Reuters, referring to the stock market rally in the wake of Trump's election.
However, losses on Wall Street Thursday were curbed as corporate earnings continue to show strong results for the quarter. Comcast was the top boost to the benchmark S&P 500 index after its results.
"You still have this upward press of real solid earnings and good economic data, but if this deteriorates at all you are going to have a blow down," said Siomades.
U.S. economic data showed new orders for key U.S.-made capital goods rose less than expected in March, but a second straight monthly increase in shipments suggested business investment accelerated in the first quarter.
The Dow Jones Industrial Average fell 11.39 points, or 0.05 percent, to 20,963.7, the S&P 500 lost 1.11 points, or 0.05 percent, to 2,386.34 and the Nasdaq Composite added 16.81 points, or 0.28 percent, to 6,042.04.
Europe's main bourses fell as much as 0.5 percent as traders pulled back after a six-session winning streak on relief at the outcome of the first round of France's presidential election and encouraging earnings.
The pan-European FTSEurofirst 300 index lost 0.21 percent and MSCI's gauge of stocks across the globe shed 0.15 percent to retreat from a record.
As widely expected, the ECB made no changes to its record low interest rates or stimulus program, but euro zone government bond yields and the euro fell after Draghi said policymakers did not discuss removing the bank's easing bias on monetary policy at this month's meeting.
The benchmark 10-year Bund yield was last down almost 5 basis points at 0.302 percent. The euro was down 0.34 percent to $1.0866 against the dollar.
The Canadian dollar and Mexican peso went in opposite directions after the U.S. said it would not scrap the North American Free Trade Agreement (NAFTA).
The Mexican peso strengthened 0.53 percent versus the U.S. dollar at 19.08.
The Canadian dollar weakened 0.32 percent versus the greenback at 1.37 per dollar.
Microsoft, Amazon.com and Google parent Alphabet are scheduled to report results after the closing bell on Wall Street. First quarter earnings are expected to show growth of 12.4 percent, according to Thomson Reuters data, those most since 2011.
Oil prices retreated after news that two key oilfields in Libya had restarted, pumping crude for export into an already bloated market.
U.S. crude fell 2.5 percent to $48.38 per barrel and Brent was last at $51.12, down 2.46 percent on the day.
Editing by Bernadette Baum