TOKYO, Jan 14 (Reuters) - The dollar extended its rebound from near three-year lows versus major peers on Thursday, supported by higher U.S. yields, as President-elect Joe Biden prepared to outline his plans for massive fiscal stimulus.

The dollar index held onto gains made on Wednesday in early Asian trading as investors continued to unwind bearish bets. The dollar has risen in four of the past five trading sessions as the prospect of more stimulus has weighed on U.S. government bonds, sending the benchmark Treasury yield above 1% for the first time since March.

Bitcoin also held on to 10% gains made on Wednesday as it rebounded after sliding almost $12,000 from an all-time high of $42,000 hit last week.

Biden will give details on Thursday of a plan for "trillions" of dollars in pandemic relief. Expectations that more stimulus will fuel faster growth has lifted U.S. yields, which in turn supported the dollar.

However many analysts expect the currency's bounce to be temporary, as a build up of bearish dollar positions are shaken out. Longer term, they expect more U.S. stimulus to support risk sentiment, weighing on the greenback, which is traditionally considered a safe-haven.

"I think positioning in risk assets is becoming a concern, so there could be a squeeze in the dollar near-term," said Shusuke Yamada, chief Japan FX strategist at Bank of America in Tokyo.

"I am focusing on gradual dollar weakness in 2021."

FX speculators have been net short the dollar since mid-March, as investors' surging appetite for riskier assets hurt demand for the greenback.

The dollar index traded little changed at 90.292 after adding 0.3% overnight. It fell as low as 89.206 on Jan. 6 for the first time since March 2018.

The euro was largely steady at $1.2164 after sliding 0.4% on Wednesday.

The greenback was little changed at 103.925 yen , following a 0.1% rise previously.

Bitcoin was 0.6% higher at $37,655 on Thursday, up from as low as $30,261.13 on Jan. 11. ========================================================

Currency bid prices at 10:06AM (106 GMT)

Description RIC Last U.S. Close Pct Change YTD Pct High Bid Low Bid

Previous Change

Session

Euro/Dollar $1.2165 $1.2159 +0.05% -0.43% +1.2171 +1.2155

Dollar/Yen 103.8670 103.8850 +0.01% +0.59% +103.9200 +103.8150

Euro/Yen 126.37 126.28 +0.07% -0.43% +126.4300 +126.2300

Dollar/Swiss 0.8871 0.8875 -0.04% +0.28% +0.8877 +0.8871

Sterling/Dollar 1.3651 1.3637 +0.10% -0.09% +1.3651 +1.3644

Dollar/Canadian 1.2686 1.2701 -0.10% -0.36% +1.2699 +1.2688

Aussie/Dollar 0.7749 0.7734 +0.20% +0.74% +0.7750 +0.7733

NZ 0.7191 0.7175 +0.24% +0.15% +0.7193 +0.7182

Dollar/Dollar

All spots Tokyo spots Europe spots Volatilities Tokyo Forex market info from BOJ

<^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ World FX rates

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^>

(Reporting by Kevin Buckland; Editing by Ana Nicolaci da Costa)

((Kevin.Buckland@thomsonreuters.com;))