The dollar was on track for its worst yearly loss since 2017 on Thursday as expectations of additional fiscal stimulus and loose Federal Reserve monetary policies lead investors to shun the currency and project further weakness in 2021.

An improving economic outlook as COVID-19 vaccines are rolled out and unprecedented fiscal and monetary stimulus has dimmed the allure of the greenback.

The U.S. currency is also suffering from rising fiscal and current account deficits that show no signs of slowing down.

The dollar was little changed against a basket of currencies  at 89.59, after earlier dropping to 89.52, the lowest since April 2018. It is down more than 7% this year.

The euro slid 0.16% to $1.2281 after reaching $1.2310 on Wednesday, the highest since April 2018.

The dollar slipped 0.18% against the Japanese yen to 103.07  yen. It is holding just above a nine-month low of 102.86 yen reached on Dec. 17.

U.S. Senate leader Mitch McConnell dealt a likely death blow on Wednesday to President Donald Trump's bid to boost coronavirus aid to Americans, declining to schedule a swift Senate vote on a bill to raise relief checks to $2,000 from $600.

However, U.S. President-elect Joe Biden is expected to push for more measures to support the U.S. economy after he is inaugurated next month.

Investors are also watching runoff elections in Georgia for two Senate seats next month that will determine which party controls the Senate. If the Republicans win one or both of the Georgia seats, they will retain a slim majority in the chamber and can block Biden's legislative goals and judicial nominees.