(Reuters) - Global tech giants halved their business flight emissions in 2023 compared to 2019, but companies like Apple ( AAPL ) and Google's parent Alphabet are falling behind, risking a return to pre-pandemic levels, a Brussels-based NGO said in a report.

Business travel last year approached pre-pandemic levels but trailed behind leisure trips, as geopolitical conflicts and a slower rebound in key markets hindered full recovery.

Emissions from corporate flights by 26 major tech companies analysed by Travel Smart, a campaign led by Transport & Environment (T&E) dropped by an average of 49% in 2023, it found.

While this shows that many tech firms are on the right path, only seven have set specific reduction targets that are essential to keeping business flight numbers in check, T&E said.

Alphabet, which has not set a goal to cut emissions, and Apple ( AAPL ), which set a broader target, are slowly creeping back toward 2019 levels, T&E said.

The two were among the worst performers, with reductions in corporate travel emissions of just 23% and 31% in 2023, respectively.

"How can (Google chief) Sundar Pichai say that Google is progressing to a sustainable future when its travel emissions are going in the wrong direction?" said Denise Auclair, corporate travel manager at T&E.

Microsoft ( MSFT ), IBM ( IBM ), and SAP, despite significant cuts, are also at risk as they are among the companies that fly the most without having set reduction goals, T&E said.

"Tech companies have claimed to be climate leaders for a long time and many have substantially reduced their business travel emissions, but if they want to be credible they must set reduction targets," Auclair added.

Asked about its performance, Apple ( AAPL ) said it has already reduced its greenhouse gas emissions by more than 55% since 2015 as part of its goal to become carbon-neutral by 2030.

"We're achieving this by making reductions across our entire carbon footprint - including business travel - and implementing significant cuts to the largest sources of our emissions," a spokesperson for Apple ( AAPL ) told Reuters.

Other companies were not immediately available for comment.