diff --git a/build/rust/cargo_crate.gni b/build/rust/cargo_crate.gni
index a1c0abc..6e0ea2b 100644
--- a/build/rust/cargo_crate.gni
+++ b/build/rust/cargo_crate.gni
@@ -307,11 +307,9 @@
       if (defined(invoker.allow_unsafe)) {
         allow_unsafe = invoker.allow_unsafe
       }
-      rustflags +=
-          [ "-Awarnings" ]  # Suppress other warnings in 3rd-party crates.
-
+      configs += [ "//build/rust/cargo_crate:allow_all_warnings" ]
 
       if (!defined(build_native_rust_unit_tests)) {
         build_native_rust_unit_tests = _crate_type != "proc-macro"
diff --git a/build/rust/cargo_crate/allow_all_warnings.rsp b/build/rust/cargo_crate/allow_all_warnings.rsp
new file mode 100644
index 0000000..fc112c8fa
--- /dev/null
+++ b/build/rust/cargo_crate/allow_all_warnings.rsp
@@ -0,0 +1,97 @@
+-Aabsolute_paths_not_starting_with_crate
+-Aambiguous_associated_items
+-Aambiguous_negative_literals
+-Aarithmetic_overflow
+-Abinary_asm_labels
+-Abindings_with_variant_name
+-Aclosure_returning_async_block
+-Aconflicting_repr_hints
+-Adangerous_implicit_autorefs
+-Adefault_overrides_default_fields
+-Adeprecated_in_future
+-Adeprecated_safe_2024
+-Aderef_into_dyn_supertrait
+-Aedition_2024_expr_fragment_specifier
+-Aelided_lifetimes_in_associated_constant
+-Aelided_lifetimes_in_paths
+-Aenum_intrinsics_non_enums
+-Aexplicit_builtin_cfgs_in_flags
+-Aexplicit_outlives_requirements
+-Affi_unwind_calls
+-Afuzzy_provenance_casts
+-Aif_let_rescope
+-Aill_formed_attribute_input
+-Aimpl_trait_overcaptures
+-Aimpl_trait_redundant_captures
+-Aincomplete_include
+-Aineffective_unstable_trait_impl
+-Ainvalid_atomic_ordering
+-Ainvalid_doc_attributes
+-Ainvalid_from_utf8_unchecked
+-Ainvalid_null_arguments
+-Ainvalid_reference_casting
+-Ainvalid_type_param_default
+-Akeyword_idents_2018
+-Akeyword_idents_2024
+-Alet_underscore_drop
+-Alet_underscore_lock
+-Alinker_messages
+-Along_running_const_eval
+-Alossy_provenance_casts
+-Amacro_expanded_macro_exports_accessed_by_absolute_paths
+-Amacro_use_extern_crate
+-Ameta_variable_misuse
+-Amismatched_lifetime_syntaxes
+-Amissing_copy_implementations
+-Amissing_debug_implementations
+-Amissing_docs
+-Amissing_unsafe_on_extern
+-Amultiple_supertrait_upcastable
+-Amust_not_suspend
+-Amutable_transmutes
+-Anamed_asm_labels
+-Ano_mangle_const_items
+-Anon_ascii_idents
+-Anon_exhaustive_omitted_patterns
+-Aoverflowing_literals
+-Apatterns_in_fns_without_body
+-Aproc_macro_derive_resolution_fallback
+-Apub_use_of_private_extern_crate
+-Aredundant_imports
+-Aredundant_lifetimes
+-Arust_2021_incompatible_closure_captures
+-Arust_2021_incompatible_or_patterns
+-Arust_2021_prefixes_incompatible_syntax
+-Arust_2021_prelude_collisions
+-Arust_2024_guarded_string_incompatible_syntax
+-Arust_2024_incompatible_pat
+-Arust_2024_prelude_collisions
+-Asingle_use_lifetimes
+-Asoft_unstable
+-Asupertrait_item_shadowing_definition
+-Asupertrait_item_shadowing_usage
+-Atail_expr_drop_order
+-Atest_unstable_lint
+-Atext_direction_codepoint_in_comment
+-Atext_direction_codepoint_in_literal
+-Atrivial_casts
+-Atrivial_numeric_casts
+-Aunconditional_panic
+-Aundropped_manually_drops
+-Aunit_bindings
+-Aunknown_crate_types
+-Aunnameable_types
+-Aunqualified_local_imports
+-Aunreachable_pub
+-Aunsafe_attr_outside_unsafe
+-Aunsafe_op_in_unsafe_fn
+-Aunstable_features
+-Aunused_crate_dependencies
+-Aunused_extern_crates
+-Aunused_import_braces
+-Aunused_lifetimes
+-Aunused_macro_rules
+-Aunused_qualifications
+-Aunused_results
+-Auseless_deprecated
+-Avariant_size_differences
diff --git a/build/rust/cargo_crate/BUILD.gn b/build/rust/cargo_crate/BUILD.gn
new file mode 100644
index 0000000..bcbe13d
--- /dev/null
+++ b/build/rust/cargo_crate/BUILD.gn
@@ -0,0 +1,29 @@
+# Copyright 2025 The Chromium Authors
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# The `allow_all_warnings` is meant to be used for suppressing warnings in
+# third-party crates coming from crates.io (ones under `//third_party/rust`).
+# Note that Chromium still wants to deny most warnings in some notionally
+# "third-party" code like `//third_party/skia` or `//third_party/crabbyavif`.
+config("allow_all_warnings") {
+  rustflags = [ "-Awarnings" ]
+
+  # Ideally we would just use `-Awarnings` or `--cap-lints=allow`, but this
+  # interacts in undesirable ways with other requirements - see
+  # https://github.com/rust-lang/rust/issues/143108 for more context.
+  # So, to work around that, we explicitly allow individual warnings
+  # (because `-Amore-specific-warning` will win over
+  # the less specific `#![deny(warnings)]`).
+  #
+  # `allow_all_warnings.rsp` has been initially generated by taking the output
+  # of `rustc -W help` and then manually removing entries for warnings
+  # explicitly controlled by gni templates (e.g.  `unsafe_code` warning covered
+  # by `//build/rust:forbid_unsafe`).
+  #
+  # TODO(https://crbug.com/428207407): Stop suppressing individual warnings
+  # once a single flag can reliably suppress all warnings.
+  _path = rebase_path("allow_all_warnings.rsp", root_build_dir)
+  rustflags += [ "@${_path}" ]
+  inputs = [ "allow_all_warnings.rsp" ]
+}