* Pound hits 2 1/2-year high as EU chief says agreement closer * Bitcoin rises to all-time high above $22,000 * Graphic: World FX rates in 2020 tmsnrt.rs/2RBWI5E By Kevin Buckland TOKYO, Dec 17 (Reuters) - The dollar set fresh 2-1/2-year lows against major peers including the British pound and euro on Thursday as progress toward agreeing a U.S. stimulus package and a Brexit deal boosted risk appetite at the expense of the safest assets. Congressional negotiators were "closing in on" a $900 billion COVID-19 aid bill, lawmakers and aides said on Wednesday, with the tone the most positive it"s been in months. Across the Atlantic, the European Union"s chief executive said a deal with the UK was nearer, although success wasn"t guaranteed. "As the world gets more optimistic about the outlook for growth in 2021, the dollar has softened," said Michael McCarthy, chief strategist at broker CMC Markets in Sydney. "Further weakening of the dollar is on the cards." The dollar index sank as low as 89.97 in Asian trading, breaking below 90 for the first time since April 2018. The euro changed hands at $1.22305, after earlier reaching $1.2235, also the strongest since April 2018. The pound bought $1.3557 having risen to $1.3564 for the first time since May 2018. The Federal Reserve on Wednesday vowed to keep funnelling cash into financial markets until the U.S. economic recovery is secure, a promise of long-term help that fell short of some investors" hopes of an immediate move to shore up a recent pandemic-related slide. The dollar index jerked higher after the Fed"s announcement, but the respite was short-lived. "The U.S." long-term yield is too low to finance its current account deficit," said Minori Uchida, chief currency strategist at MUFG Bank in Tokyo. "As long as U.S. long-term yields stay at very low levels, the dollar will be weaker," with scope to fall by as much as 10% against rivals like the euro, yen and Chinese yuan, he said. The greenback slid to 103.280 yen, also a safe haven currency, and Uchida said it could break 100 by March. The onshore yuan traded at 6.5369 per dollar, while its offshore counterpart changed hands at 6.5117, near the 6.4975 level it reached earlier this month for the first time since June 2018. Meanwhile, the Swiss franc was little changed after touching a six-year high of 0.8826 per dollar on Wednesday, when the U.S. Treasury labeled Switzerland a currency manipulator. The Treasury said that through June 2020 both Switzerland and Vietnam had intervened in currency markets to prevent effective balance of payments adjustments. In Europe, while talks for a trade deal have progressed, fishing rights remain a particular sticking point as the UK prepares to exit the trading bloc at the turn of the year. British Prime Minister Boris Johnson"s aide said on Wednesday that no deal was still the most likely outcome. "Forex traders appear largely unfazed by the possibility of a no deal exit," said CMC"s McCarthy. "The strength in sterling is remarkable." The Australian dollar touched 75.975 U.S. cents, the highest since June 2018. Its New Zealand peer reached 71.41 U.S. cents, a level unseen since April 2018. Bitcoin traded as high as $22,394 after smashing through the $20,000 barrier for the first time overnight. "Bitcoin is still on its latest tear," Ray Attrill, head of foreign exchange strategy at National Australia Bank in Sydney, wrote in a client note. "I still don"t want one for Christmas." ======================================================== Currency bid prices at 3:45PM (645 GMT) Description RIC Last U.S. Close Pct Change YTD Pct High Bid Low Bid Previous Change Session Euro/Dollar $1.2228 $1.2202 +0.22% +9.08% +1.2235 +1.2189 Dollar/Yen 103.2500 103.4350 -0.14% -4.90% +103.5470 +103.2750 Euro/Yen 126.26 126.19 +0.06% +3.53% +126.3800 +126.0600 Dollar/Swiss 0.8837 0.8849 -0.10% -8.64% +0.8857 +0.8838 Sterling/Dollar 1.3552 1.3511 +0.33% +2.21% +1.3562 +1.3499 Dollar/Canadian 1.2712 1.2738 -0.19% -2.13% +1.2749 +1.2711 Aussie/Dollar 0.7593 0.7579 +0.22% +8.24% +0.7596 +0.7568 NZ 0.7133 0.7114 +0.30% +6.03% +0.7138 +0.7104 Dollar/Dollar All spots Tokyo spots Europe spots Volatilities Tokyo Forex market info from BOJ (Editing by Shri Navaratnam and Jacqueline Wong & Shri Navaratnam)