Royal Dutch Shell (RDSA) has asked the Obama administration for five more years to explore for oil off Alaska’s coast, saying setbacks and legal delays may push the start of drilling past expiration of some leases, according to Bloomberg.

The conservation group Oceana obtained a copy of the July 10 letter requesting the extension through a public records request. In the letter, Shell argued that legal disputes, seasonal drilling restrictions and other challenges justify the additional time, according to Fuel Fix

Without the extension, Shell’s oil and gas leases in the Chukchi and Beaufort seas will begin to expire in 2017.