* Graphic: World FX rates in 2019 http://tmsnrt.rs/2egbfVh
By Daniel Leussink
TOKYO, April 23 (Reuters) - The dollar trod water against other major currencies in early Asian trade on Tuesday, while the Canadian dollar was supported by rising crude oil prices due to U.S. plans to tighten a clamp down on Iranian oil exports from next month.
Financial markets in Australian and New Zealand reopened after the long Easter holiday, and were set to reopen across Europe later in the day.
The dollar index against a basket of six key rivals was a shade higher at 97.345 .DXY , still near a 2019 high of 97.71 struck in early March.
The greenback has firmed in recent weeks on the back of higher U.S. 10-year Treasury yields US10YT=RR and signs of strength in the U.S. economy following a weak start of the year.
Data released overnight showed U.S. existing home sales fell more than expected in March amid supply constraints, and figures for new home sales will be released later in the global day. those may provide some pointers to the state of the U.S. economy, a clearer picture should emerge from the gross domestic product report set for release on Friday.
"Investors will be looking for an increase in volatility in the days ahead as traders return to desks and earnings season in the U.S. steps up," said Nick Twidale, chief operating officer at Rakuten Securities Australia in Sydney.
"This week could give a strong indication of whether the dramatic dovish turn from global central banks, and in particular the Fed, over the last few months has been enough to change the global growth dynamic," he said in a note.
The dollar edged down 0.1 percent to 111.84 yen JPY= , moving off a high for this year of 112.17 hit last Wednesday.
The greenback's moves against the euro and sterling were small, with those units largely holding steady at $1.1252 EUR= and $1.2975 GBP=D4 , respectively.
The Canadian dollar held firm after oil prices rallied to near six-month highs overnight on news that Washington plans to eliminate waivers next month for eight countries to buy Iranian oil without facing U.S. sanctions. the jump in the price of oil, one of Canada's major exports, the loonie held steady at $0.7492 CADUSD=R , having gained more than a third of a percent during the previous session.
(Editing by Simon Cameron-Moore)