(Reuters) -European shares were mixed on Tuesday as investors assessed the latest phase of U.S. President Donald Trump's tariff rollout, which included new proposals for several countries and a new deadline for trade deals.

The pan-European STOXX 600 index down 0.1% at 542.73 points, as of 0836 GMT.

Other regional indexes were mixed, with Germany's DAX and the UK's FTSE 100 gaining 0.1% each. While France's CAC 40 fell 0.3% and Spain's IBEX was flat.

Trump signed an executive order on Monday, extending the date on which the "reciprocal" tariffs will take effect to August 1, from the previous deadline of July 9.

However, he said that the deadline was not 100% firm and he would consider extensions if countries made proposals.

Also on Monday, Trump sent letters to 14 countries, including powerhouse suppliers like Japan and South Korea, unveiling sharply higher tariffs on imports to the U.S. starting August 1, marking a new phase in the trade war he launched earlier this year.

"There's lingering uncertainty about what's going on as far as Trump's trade tariffs are concerned...it's not giving investors any impetus to really take a direction one way or the other until they have more information", said Fiona Cincotta, senior market analyst at City Index.

Cincotta said Trump's openness to negotiation adds a slightly positive spin, but noted that "any gains will be very limited due to ongoing uncertainty."

Countries have been under pressure to seal deals with the U.S. after Trump launched a global trade war in April, which rattled financial markets and prompted policymakers to scramble to protect their economies.

Back home, the European Union will not receive a letter from the U.S. setting out higher tariffs, EU sources told Reuters on Monday.

The bloc, which is yet to agree on a trade deal with the U.S., still aims to reach an agreement by Wednesday, the original July 9 tariff deadline.

In the market, European real estate shares fell 1%, while basic resources were up 0.9%.

Among individual stocks, Kinnevik rose 5.1%, to the top of the benchmark index, after the Swedish investment company posted 2% quarter-to-quarter growth in its second quarter net asset value.

Zealand Pharma gained 3.5% after Barclays initiated coverage of the Danish biotechnology company with an "overweight" rating.

Conversely, Handelsbanken fell 1.4% after Morgan Stanley downgraded the Swedish bank to "underweight" from "equal weight".

On the data front, German exports fell more than expected in May as demand from the U.S. decreased for the second consecutive month following a period of strong purchases in anticipation of U.S. tariffs.